5 rd. mag was more or less flush in the old XRay, 10 rd. mag stuck out a bit, should be same on Bravo (and you used to have to reach up into the magwell to get at the mag release lever).
What SourMash said. I am running a Bravo on my T1x and I have shot my friends CZ in a Bravo quite a bit. The cutout for the mag well is the size of AICS mags so there is plenty of room for your fingers to reach up in there. I usually hold the mag with my thumb and middle finger and put my index finger on the front of the mag well and let the front of the magazine ride that up to the mag well. That makes mag changes on the clock really quick.