I used to pre wash everything too, then I had to use some unwashed fabric in a quilt mixed with pre-washed, and there was not a single bit of difference.

I used to also prefer the way washed fabric handled, but now that I am quilting, it IS easier to cut and sew unwashed. I am a creature of habit and like familiarity, but let me say that I VERY quickly became familiar to sewing with unwashed fabric!

And there is no noticeable difference in the wrinkliness of the finished quilt either way after it's washed and dried. Most of today's quilting cottons shrink very minimally, so don't worry your quilt won't look as 'quilty' if you do wash first.