Montu - For me this is the best one. It's big, it badass and it has a Batwing. <3
Nemesis - Probably the most unique layout, and has some awesome forces. Why Nemesis is good has been done to death, so I don't feel like I need to say more.
Batman Clones - The Batman clones are amazingly intense and I love their compact layouts. They're only just behind Nemesis as there's something about their more traditional layout that isn't as interesting. They do kick-ass though!
Talon - Good all rounder. I do like the second little drop into the corner before the wingover, it's a nice pop of airtime and something a bit different.
Patriot - Most of Patriot is pretty tame, except for the zero-G. I mean tame by B&M Invert standards mind, it's still a good ride, but it's got by far the best zero-G of any coaster I've been on. Perfect floater, no violent whipping, just ideal.
Raptor - It didn't stand out for me as being anything special, but I remember it being a good solid ride.
Nemesis Inferno - Another good one, but nothing amazing.
DC Chinese Fireball & DC Hungarian Horntail - Lets face it, individually these rides are pretty crap. It's only the interaction that makes them remotely interesting.
So there are my choices in order, but as Furie said, they're all great rides and there's not a lot between them all to be honest.