I went with younger, though right now I think they'd be too young, I mean, girls at my age aren't very mature, so I'll have to wait a few years to get serious with one, unless I find a real gem, aka, a young girl with her head on her shoulders.
There are issues going older and younger. The problem with some older people is they get set in their ways and may have been a freak back in the day but now refuse to do certain things like they used to because they are "parents now" or "too old for that". Examples include blowjobs, hand jobs, making out, grooming "downstairs" just to name a few. The problem with younger might not be physical, but if you want a long-term relationship what you can connect with them on is going to be somewhat limited by generational life experiences or the lack thereof in some cases.
Same Age. Technically speaking I'm OK with dating guys between 18 and 30 ( 2 years younger maximum and 10 years older maximum). But for me the PERFECT bracket would be 19-27. I'm not into guys over 30 and I don't want to be with someone significantly younger (Not that it's legal for me anyways atm xD).