Nobody is going to measure the seam allowance on your finished product. As long as the pieces end up being the correct size the exact size of the seam allowance is not all that important as long as it doesn't get too skimpy.

I don't think it matters as long as each block in a quilt is made the same way. I know a woman who made a few quilts with 1/2 inch seams and then trimmed them down, she hated sewing the scant 1/4 seam. Personally I try and sew my quilts with the scant 1/4" seam. My one sewing machine doesn't do well at that, so it more like a true 1/4" seam. I try to keep all my blocks at that machine and not switch.