A Sith taking betrayal personally is kinda funny
They kill there masters as soon as there back is turned.
If anything i respect Quinn more for believing he could defeat a Sith lord, and fully expecting to die for failing, he acted more like a Sith then an Imp.
This. Baras called and wanted his favor cashed in, Quinn is an honorable guy, so he did it. He didn't sound thrilled to do it and didn't even sound like he expected to live afterwards. Betrayal is how Sith roll, so I can respect that. I don't have to like it though. As my healer, he's definitely useful and it would be dumb to kill him. I can see Bioware adding more to this later, maybe in Act 4 whenever it comes out.
I'M A SITH LORD, I KILL EVERYTHING is dumb. He's useful, use him. When he's no longer useful, you can have your revenge then.