I'm also of the round up and trim down persuasion. I am working on Friendship Stars for two of the nieces and found that I could get better finished squares by doing it this way. I figured I was just an amateur hack, but I'm glad to see that some of you more experienced quilters do it this way too. I briefly considered that I was wasting fabric, but I figured the price was worth getting accurate blocks. The first couple that I did were nightmares b/c the sizes weren't exactly right, but the stars look great now. Maybe someday I'll get more accurate, but for now I'm perfectly fine doing it this way.
Darren