I would say that size is not an issue for me. Though as you say "watermelon breasts" would probably be more of a turn off.

So are talking about tits or breasts?

I guess more of a turn on would be how a woman responded to breast caressing. From what I understand overly sized breats aren't capable of that much pleasure because the nerves are too "streched" over the surface, while smaller ones can be more sensitive. For comparizon look at the ancient chinese practice (which TG has been banned) of making womans feet unaturally small. I heard it was quite easy to arouse and bring to orgasm a chinese woman by just massaging their feet.

__________________
.sixsense.