Yeah, if the OP wants the 25, then 12-25 is the way to go. Although, if you're climbing enough to want a 34x25 combo, you might find yourself lacking in 50x12 going down the other side. But it also depends what type of riding the OP is doing... if he/she is racing or doing club hammerfests, I'd recommend going to the 11-23 and suffering for a little until he/she adapts. But for most people riding for the sake of riding, 12-25 should be perfect.