My "Girls" need some help!
A "good" exercise bra will really depend on what cup size you are and what kind of activity you plan to do. You are likely to get support and some lift, but there is usually some "squishing" especially once you get some loose skin in that area from weight loss.
I'm down to a C now and I'm a big fan of Moving Comfort's Maia bra - I was really surprised just how comfortable an underwire sports bra could actually be - and the wires have NEVER popped out despite many many miles of running, spinning etc in them!
I think that the moving comfort website has a "bra finder" to help you get started....
The miracle isn't that I finished...the miracle is that I had the courage to start -- John "The Penguin" Bingham
I recently bought a couple Danskin underwire sports bras and Wal-mart and seriously LOVE THEM! I actually wear them for every-day use too. I've got from a D to B cup and these make it look like I actually have breasts.. and I feel very secure and supported working out as well. They were only $10 too. bonus.