My order would be:

2003/2004 Cobra

2005 GTO

2002 Camaro SS, TransAm WS6 (they are not bad to work on, and don't have a lot of problems. I have a '98 With a ton of miles and it dosnt give me any trouble

Mach 1

EVO

STi...

not really an import guy, but I'd take an EVO or STi if I was forced to get one

Everyones opinions are going to be on what they like, and not real facts. Every single one of those cars have "notorious" problems that other people will mention.. But it comes down to getting what you want. Go drive them and then see what you like the most