*I* would leave it. I noticed a flaw with one I made a while back...I noticed it before I even sewed it together. It would have been an easy fix, but the truth is, I don't care that much. Might sound bad, but I have no interest in being perfect. The exception would be if this were a customer quilt. I will absolutely fix a flaw in a quilt someone is paying me for, assuming I notice it before quilting. If I don't...? Then I'll just hope they don't either, because unless the quilting is really screwed up, I'm *not* ripping out quilting stitches.