I posted on that thread last year--look, the question has come up again! Here's my 2 cents, as an athletic 34DD:

I have used that Enell (size 1) for a couple of triathlons. However, it has been sitting in my drawer for the last year because I can't bring myself to put it on. First, it is so constraining, it feels like a girdle. Second, it is very thick and makes a thick line under any tank top--doesn't look great. Maybe someone out there would want mine? I don't think I want it anymore.

I like the Hind Motion Sensor and was actually thinking of wearing it for my next triathlon. Especially since I'll be swimming in a wetsuit. I don't know if it would offer enough coverage and support as a bathing suit top.

Two more I like a lot: the Champion Friction Free™ Seamless Full Support Sports Bra, which has a lot of support but may be discontinued, and the Road Runner Sports Sporktek Bra. (Susan recommended this last year!) I have two of the Sporteks and wear them every week. However, they are a bit thick so might not be great for a tri swim.

Good luck!