For the most part, as long as you keep a good attitude towards UPT, instruction, etc, prior flying time can only help you. With the exception of one guy, all of us who got fighters in my class had prior flight time ranging from 80 hrs to 900 hrs. I think it helps and strongly suggest anyone get time. Not only will it help you, but it will be fun. Obviously experiences differ between classes, but bottom line is it's never a bad idea to get flight time.