I almost always fap with my imagination over local women I know - some of whom I've already banged in the past. And most of them are not quite dimepieces - some are even pretty ordinary by getbigger standards.
I used to have a bad habit when I was younger of screwing chicks who were already involved in other relationships. I would often go after friends' sisters, their ex-girlfriends, and even their mothers on occasion.
The first woman I ever fapped to some 30 years ago was the busty, full-figured, slightly above average looking early-30's mother of a buddy a couple of years younger than me. I was eventually able to nail her some 20 years later when I was a mid-30's degenerate horndog, and she was a horny, slightly plump, early-50's recently divorced cougar with even bigger tits than before.