I've had couple gf's who had fairly large vaginas and both were fairly slim and small otherwise. I do prefer larger vaginas as it's easier to penetrate than a tight one even well aroused and wet, and after sex as the (preferably large and thick) swollen labia has turned on the sides and the vaginal entrance has become a gaping hole it's an immense pleasure to watch the vaginal walls pulse post-orgasm and semen pooled in the bottom until she started to squeeze it out.
The sensation (to my penis) with a large vagina is much more subtle than with a tight one and in a sense more intimate. Though I had one one night stand who honestly had a Grand Canyon (I'm not less than average) and I did have to decide which of the four directions I should poke to have the best arousal for my penis.
I have noticed that bigger women have tighter vaginas, and have enjoyed sex with tight big girls immensely too.