When I was a younger guy, a long long time ago, I typically liked the big boobage and blonde hair. Completely the opposite today...
When I was 17 I had a girlfriend with 36 D's that she hid really well from the general public. I thought they were cool as hell until the bra came off and they about fell to her knees. If that's what she was like at 17 I can't imagine what they're like now. Though, when she was on her back it was kinda cool to watch them swirl around like a couple of fried eggs on a skillet. No, really... think about it.
I'm not really a breast guy these days. Any size is good if I'm into the person, but I am definitely not a fan of surgical enhancement. If given the choice, I think smaller is preferable to than larger. But that's me...