I think it's Quentin, too. My other prime suspect is Dr. Bobolitt from first season. He wanted to trade Christian a sports car for Kimber and his career was basically destroyed by Sean and Christian. Then he accidentally killed someone in his massage parlor chop shop and was basically going nuts.
I read it could be a woman, too. But screen shots of the carver make the character look very masculine in terms of build. So I think it's a guy. If it *had* to be a woman, I would suspect Liz or Julia, because Liz is a dr. and Julia had some pre-med, so they'd have the medical knowledge to do the carving as precisely as the police said it was done.
Too bad it's not Matt. The police could "accidentally" shoot him a few times.
this order: dr. bobolitt, ava, matt (just cuz i don't like him and i think he has the motivation...although last week with him and christian made me kinda like him more).
__________________
"i tell you one lesson I learned
If you want to be something in life, You ain't gonna get it unless, You give a little bit of sacrifice, Oohh, sometimes before you smile you got to cry.." -The Roots