I went up a cup size as advised and I can get it on but it's too small to adjust to a racerback. I was advised it was similar to the Brooks Juno but it's nowhere near as supportive for running. I'll probably only wear it for ow impact activities.
This is not a bad sports bra, it's just not the best I've worn. It's comfortable to wear, with no rubbing or chafing. I just didn't feel as supported wearing it for running and HIIT workouts as I do wearing other bras. It's definitely less rigid than the older style Brooks wireless sports bra - and less supportive. I'll still wear this one, but I probably won't buy any more.