I guess that question pops up when there's a significant age difference between a couple. For instance, you wouldn't want to date someone that's 14 or something when you're about to graduate high school, but you'd date a college hottie at the same time, right? I would! But when you're in college you probably won't want to date someone that's 16 b/c you gotta wait till they're legal or even mature enough to do practically anything and you'd have to drive em around everywhere. There's a lot of variation with it in countries, laws, standards of living, but ultimately I'd agree; what matters most is the person.

Hmm but if I had to set limits or something my personal chart would go something like eh..

Age 13: 13-16
Age 18: 17+
Age 21: 18-30
Age 30: 20-35
Age 35: 18-45
Age 45: 25-44

If  not settled by 45, consider becoming a swinging shagger or something or another..

*Age 30: 21-35

but really who knows?