I also vote for the Classics Prime. It is definately my favorite Prime too. He is really well proportioned, has great articulation, and just is a fun toy to play with because of the very little kibble or excesive parts. The movie leader is cool, I will grant, but it's almost too big to really play with. There are just too many parts that slide and wiggle when you just want to pose him and stuff. The voyager movie prime I definately dislike. I'm actually wanting to get rid of my Robovision one.
Classics Prime is a really nice re-imagining of the original version. Some things were changed to update him but the articulation is nice and useful and the robot mode takes precedence over the alt. mode, which is always what I prefer. As far as movie Primes I can see why some people like Leader Prime, but Voyager Prime seems a lot more movie accurate to me. He is a little bit smaller but when you place him up against the Autobots (except for Ratchet who seems too big) he looks pretty nice. There is also some imagery that make Megatron look massive compared to Prime so if you go by those pictures the Leader megs and the Voyager Prime are closer in scale then the Leader Prime and Megatron. It's all a matter of opinion though. The look of the Autobots have really grown on me since I saw the movie but nothing can really replace their iconic looks.
As far as the voyager class goes, I say Classics all the way. Voyager movie Prime has never impressed me much, while Classics Prime is a pretty damn amazing figure (even with the major arm kibble). But Classics. vs. Movie in general? I'd take leader class Optimus any day. He is, hands down, the best damn Optimus Prime figure ever, with only MP/20th coming close.
I have both. Movie Prime is HIGHLY detailed and has cool weapons, but I find his large feet and back kibble make posing harder than it should be. Whenever I wanna play with one, I almost always reach for Classics
Classics Prime craps all over the Voyager Movie Prime. However Movie LEADER Prime is awesome. I dunno, IMO Movie Voyager Prime is SUPER overrated. The guns are cool, the articulation is decent and the disappearing driver gimmick is sweet, but I hate the fact that half the truck mode is hanging off its back, and it's not even close to being in scale with the other movie toys. Scale in TFs is a crazy concept and it never bothered me before the movie, so yes I do realize I am a huge hypocrite in that aspect.
I'm pretty much the same way. I love Leader Prime and think he looks awesome, but I fiddle around with Classics Prime a lot more.