ToT and RnR rule in the rides category! So there's my vote for MGM.
The "mountains" are cool in MK too. But we didn't even go on "splash" last weekend because it was cool and we didn't want to get wet. I wish that there was a "switch-off" option before the hill so little children, scaredy cats and those not wanting to get wet could ride it. The ride itself is so cute, even without the big drop at the end.
We also like Test Track at Epcot, but not enough else there yet.
Not a huge fan of water rides and "Dinosaur" just ok so not AK.
I guess my vote is still for the studio!