I have gotten 5 of these sports bras and love them all.  I finally went a size up to (C-D) to criss cross the straps in the back (adjustable velco on front of bra straps) so I can wear them also with my racer back running shirts and this makes the fit very snug but comfortable. I have chafed a little on the longer runs (5-10 miles) under the lower bra band in the front when I criss cross the straps in the back but apply a little sports glide on my skin before the run and problem solved! The Fiona Sports Bra in my opinion is one of the best made support sports bras on the market that is both comfortable and well constructed to last.  Almost a complete no bounce bra with soft and wide straps that don't dig in or pinch and moisture whisking is excellent even on long runs!