I don't think this applies nowadays with so much information at our fingertips...a 3 pump chump might appear to be a Sex Master to some virgin in a remote part of the world, but any girl with access to internet will know he's no good.
I've asked myself the same question and still haven't come up with an answer. Your argument against a virgin is that she hasn't dealt with one or more shi*y guys so she's really grateful once she meets you, the good guy. My argument against this would be...does a smart person really has to burn herself before realizing it's bad to stick fingers in fire? In other words, smart people learn from other's mistakes, life is too short for one to make all the mistakes necessary for learning. My main point against a virgin is that finding a 24-25yrs old virgin who is attractive and clinically sane would be a bit like winning the lottery.
The problem I have with the 1-3 long term boyfriends is that every past boyfriend is a hit on two very important characteristics of a girlfriend: loyalty and rational thinking. I mean, a girl with top loyalty and who properly vets her boyfriend will stay with her first guy for life (I was impressed to find out about Queen Elizabeth who set her eyes on Prince Phillip when she was 13 and he 18). Now, I know life is messy and people are not perfect, but still the question remains...where's the right balance between her learning from experience and loyalty being ireparably damaged ? 1,2,3 past boyfriends?