Precuts are GREAT for a lot of projects, and that's coming from an old-timer (25 yrs) They are quick and fun. You get to see and use the whole line of fabric without all the expense. I've never had a problem with a precut.
I think the BEST thing about them is bringing a lot of younger people into quilting ... my DD and nieces love them and are sewing up a storm ! I've been teaching friends of theirs how to make their first quilts, pillows, place mats etc It takes away the intimidation factor vs. cutting into yards of fabric. They are loving it :)