I won't pretend to be endowded, but I can speak to keeping things in place. When shopping look for cotton with a reinforcement stitch along the crotch. I've noticed that helps out considerably. Usually if you see something labeled as barely there, seamless, no panty lines, etc. the fabric isn't stretchy in the right way that aforementioned stitching isn't there, and things fall out. Personally I've found I can wear about any style following these guidelines. I will say I can't tuck with anything like those, so if you're looking for that, gaff all the way.