Hind Nexus Bra: I love this bra. It provides more support than any other Hind Bra. It's also the snuggest fit. Where the Motion Sensor has stretchy straps, the entire Nexus bra is lined on the inside with a second layer of non-stretchy fabric. It's easy to see here on the inside of the black bra:
The other reason this bra is so supportive is because it has a broader back across which the weight can be distributed. See the back photo here:
Beware the front zipper. It's a locking zipper, but the zipper pull must be in the down and locked position. Otherwise you risk a spontaneous boobage explosion. Been there, done that.

I've never had the bra unzip while running or doing triathlon. BUT I have had it open up while puttering around the office, usually because I've been lifting boxes and stuff and I dislodge the zipper.