You receive this companion on Balmora.

He is a ranged DPS/Healer. He uses medium armor and a blaster pistol.

For those of you looking for the Quinn quests (since they seem to not be the easiest thing to find)...

Quinn's Quests

Malavai Quinn is a good versatile healer/ranged dps companion that Sith Warriors can get very early in the game. His healing is very effective and he's even got an ability to remove status ailments. The best part is that when he's not healing he does ranged dps so it's not a bad idea to keep his blaster up to date. While his dps is nowhere near Vette's, he's much safer to have by your side if you're venturing into an area you're not too sure about or taking on a challenging mission.

His two stances (one improves healing and one improves damage) add some versatility for when you may not be taking much damage and would prefer some extra firepower while still receiving some moderate healing and support that Vette can't provide. However, if health is not a concern, Vette will help you down enemies considerably faster.

He likes imperial memorabilia, survival gear, and people who appreciate his advice. He identifies with a lot of questgivers, and so treating them well when they've done a good job also gets you +affection. If you're irritated by Vette freaking out every time you toss off a death threat, suck up to your superiors, or mistreat one of the empire's slaves, this guy comes as a nice change of pace. Much better dark side companion. On the ship, after you recruit him, he is standing at attention by the captain's chair.

Alas, he does not keep his cool imperial agent outfit when you get him as a companion, but exchanges it for a light colored and somewhat dorky trench coat. He wears +cunning medium armor.

As a Juggernaut, I wished that I got this healing companion earlier in the game.

SPOILER
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My advice for Juggernauts is to prioritize the completion of the class quests on Balmorra to accelerate "unlocking" Quinn. He becomes one of your companions at the conclusion of the Balmorra class quests; you can complete the remaining Balmorra quests before you move on to Nar Shaddaa.

At about 3750 affection, if in a romance, Quinn confronts the player about being unprofessional. It's unclear if he's upset with you for flirting with him or with himself for being interested by this, but you do get the chance to initiate a classic terribly animated bioware kiss. No idea if there's a conversation option here if you're not in a romance.

Around 4370, Quinn requests permission to investigate another screwup by his least favorite moff. Around 4750, if granted permission, this will lead to another lightning fast mission. As usual, referring to the empire when praising him is much better than encouraging him to take personal pleasure in a bit of vengeance. It might slow me down in advancing the romance plot, but I am quite curious to see if he ever actually gets the hang of thinking like a sith. Hm.... no, probably never.

List of Customizations:

Malavai Quinn Customization 1
Malavai Quinn Customization 2
Malavai Quinn Customization 3
Malavai Quinn Customization 4
Malavai Quinn Customization 5
Malavai Quinn Customization 6
Malavai Quinn Customization 7
Malavai Quinn Customization 8
Infected Malavai Quinn Customization

Korriban
- Arm Yourself - Level 3
- Judge and Executioner - Level 4
- Slaying the Beast - Level 6
- A New Master - Level 7
- Sith Arithmetic - Level 8
- The Final Trial - Level 11 [Vette]
- Leaving Korriban - Level 11

Dromund Kaas
- The Flight to Dromund Kaas - Level 9
- The Transporter - Level 10
- Pull the Plug - Level 12
- Laying Waste - Level 14
- An Ancient Answer - Level 16
- Leaving Dromund Kaas - Level 16 - [Spaceship & Start Chapter 1]

Balmorra
- Contact Made - Level 15
- Erase the Past - Level 17
- Silence the Son - Level 18
- To Kill a Legend - Level 19 [Malavai Quinn]

Nar Shaddaa
- Seek Your Contact - Level 21
- Disrupt Negotiations - Level 21
- An Army of One - Level 22
- Distress Call - Level 22
- To Kill a Sith Lord - Level 23
- A Threat Leveled - Level 24

Tatoonie
- Seek Answers - Level 25
- Demon's Blood - Level 26
- Oasis - Level 27
- Guru in the Dunes - Level 28

Alderaan
- Shake Down - Level 28
- Knock Knock - Level 29
- Front Lines - Level 29
- Choke Point - Level 30
- Battle Organa - Level 30
- Deal with Kendoh - Level 31
- The Plan is Working! - Level 32
- The Padawan Exposed - Level 32 [Jaesa Willsaam]
- A Sith Lord's Rise - Level 32 [End Chapter 1]
- Set the Table - Level 32

Taris
- Check in - Level 32
- General Frellka - Level 32
- General Minst - Level 33
- General Durand - Level 34
- General Faraire - Level 35 [Lieutenant Pierce]

Quesh
- Ambush! - Level 36

Hoth
- Debriefing - Level 37
- Rescue Lanklyn - Level 37
- Interrogate the Talz - Level 38
- The Master's Weapon - Level 39
- Jedi Master on Ice - Level 40 [Broonmark]
- Power Play - Level 41
- Fanning the Flames - Level 41 [End Chapter 2]
- Declaration of War - Level 41

Belsavis
- Strong Arm - Level 42
- Locate the Enemy - Level 42
- A Mass of Assassins - Level 43
- Thwart the Rescue - Level 43
- Reallocation - Level 44

Voss
- Request and Audience - Level 44
- The Pain of Healing - Level 45
- Pendant of Bone - Level 46
- The Voice of Darkness - Level 47
- The Transponder Station - Level 48

Correlia
- Protect Vowrawn - Level 47
- Squeeze the Spy - Level 48
- Jedi Spy - Level 49
- Baras's Lair - Level 50
- Retribution - Level 50

I am sad to say this, but from experience so far, if you do not use this companion while you level up, you will either nearly or completely die when facing a group of mobs comprising of atleast 1 strong and several normals, going against an elite on its own, you MIGHT and i stress the world MIGHT beat it, but if you don't use your survival CDs, you will die without a doubt, if you don't use this companion.

Which is a disappointment for the Sith Warrior Class, since i would have preferred to have used a different companion, but its either this dude or nearly die or completely die, so it is obviously a class imbalance, if you NEED to use a healer companion to get the same results as a ranged class with any companion it chooses, then its obviously a problem with the class itself and i hope to see it fixed soon, but i doubt it, you know how it goes, it only gets altered if there are enough QQs in pvp.

Overall, this is a very good companion, if you are playing a female sith warrior and you like him, good for you, since you have to use him or feel like you are going through heroics all the time....yep, it feels like that all the time.

Quinn's conversations:
I: Operating Procedures
II: Peak Efficiency
III: Quinn's Grudge
IV: Missed Opportunity
V: Remedy the Past
VI: Personnel Review
VII: Seeking Advice
VIII: "My Lord"
IX: Broken Signals
X: Left Twisting
XI: Duty and Devotion
XII: "Captain, Second Grade"
XIII: Moff Broysc's Mercy
XIV: Incompetent
XV: Moff Massacre
XVI: A Better Man
XVII: Technical Changes
XVII: Tireless Commitment
XVIII: Training the Future

If I missed any write me a message and I'll add them

A) Medwatch is your friend. All the healers tend to fall out of the stance once in a while and it's hard to notice if your running the small bar.

B) Gear. Generally players that complain a comp is not doing well it is because they simply don't gear the comp appropriately ... and use a presence stim? Unheard of!

C) LoS / Pathing. That's on you ... the first time it one thing ... the second another ... but repeatedly choosing to fight in situations that will cause you Comp pathing issues is not BW's fault. All the comps use the same pathing logic ... which means dps doesn't dps, healers don't heal. You just don't notice the loss of DPS from a Comp that is stuck as easily.

In the end, if you L2P then the comps are fine no matter what role. I tend to do double DPS so I don't use healers except on my Tank Chars.

I personally hate on him because you are pretty much forced to use him the moment you get him, since otherwise you pretty much die all the time and no its not due to lack of skill, its likely a overall class survivability problem, which bioware said that they were working for both sith warrior and jedi knight classes, the problem i have is that every other class, all ranged have no problem, they can use any companion and get the same positive results, while a jedi knight or sith warrior has to use their healer companion to get that same result.

I can understand elites being difficult or challenging, since well, they are elites and i always use my Survival CDs, when i fight them, but the problem is, unless you use your healer companion, you HAVE to use those CDs against strongs, with normal adds, also the person that says to take out the weak ones first is totally wrong, in my experience, its take out the strong first, if the weaker ones die in the AoEs you do, then fine, but the stronger ones always kill me if i focus on the weaker enemies first.

I was sorely disappointed by Quinn's healing ability in the BETA, and on live, it's gotten nothing but worse.

Distance bugs his Kolto Jolt sometimes, playing the animation but giving no heal.
His already bad AI pathing is even worse up ramps/stairs, giving more LOS for heals.
His starting heals are distanced and have nearly no throughput, he spends more time shooting at stuff than healing you when you first get him. despite Med Watch.

I have lost count of the amount of times I've died due to Quinn being out of range or struggling to get into my LOS for a heal. As a vengeance warrior downtime without any healing is too much - which is why I hoped Quinn would be made infinitely more useful than he was in earlier beta builds. He wasn't.

Quinn's -one- saving grace is at higher levels, his extra heal, Medical Pack is very potent if you give him enough Cunning. It's almost as though he heals through his own stupid!

Overall though, Quinn as a healer is 'that new guy' in green gear you bring along to your raids. Not really useful until you start throwing purples at his face.

Edit: laaaawl -9. People don't like the truth it seems.