I purchased this for a triathlon. However, the material is far too loose when you go in the water such that when I swim, water comes into it in the chest area.  Not exactly race quality when that occurs.  It is not a size issue rather it is the make in my opinion. I have a TRL one piece and it is very suitable for racing. I wanted to switch to a two piece and thought given this is sold for a tri, this would be a racing feel. But it is not suitable for a tri unless you would be just as comfortable wearing a regular bathing suit in the race.  I am not going to use it for my race but unfortunately didn''t know until I tried it in pool so now I am stuck with it.

I originally bought this top in a large because I had ordered a medium TYR 2-piece suit and the top was too snug around my ribs. The large wound up being too big in the bust but fit nicely around my ribs. Because I am small-chested, the top bulged and completely ballooned out and filled with water when I swam. I wound up wearing the medium for my triathlon and was comfortable enough in it (it wasn't too snug that I couldn't breath but with my heart rate monitor under it, there was more tension that I would have liked).The sizing seems to be made for a medium-frame person with at least some chest (medium) or a medium-frame person with a lost of chest (large). I have a wide ribcage and no chest so I've struggled to find a top that fits everywhere I need it. The material of this top was perfect and super comfortable. I would absolutely recommend this top to someone doing a triathlon - hoping they have better luck in the bust area than I did.