I'm guessing by your mileage that you do road riding, correct?

36-38 D-DD here. I use underwires both for MTB and road. I've tried non-underwire on road rides and some of the less jarring MTB. They're pretty comfortable, but I find that if they don't provide separation, my forward position makes for some serious uniboob.

Champion underwires are still my favorite. I've tried some Moving Comfort models (including the Fiona) but they fit weird and the sizing seemed off. But it's always good to try them on the first time just to be sure. In fact I like to try sport bras on with a cycling jersey just to make sure everything looks and feels right.

By the way, I've read on other forums that you shouldn't use underwires (for safety?) but that was probably posted by a 34A!

Good luck,

Cari