Strapless gowns, unless very expensive designer should be illegal. I don't care how tiny you are or how low your body fat percentage may be - unless you are a professional body builder you will have back or armpit fat oozing over the top. For the bodice to remain covering your taataas it must squeeze similar to a corset and push up. It is an imobilizer. Another reason to skip strapless. You can't move. Well you do, but the gown doesn't.
If you love strapless look at ones that have lace above instead of true strapless. There are several modern dresses out there that are delicious with the appearance of strapless. Every single bride is constantly fussing with the top trying to keep it straight, covering and well, it's uncomfortable. No one wants to remember their wedding day as the day I hurt from my dress.
So that's my two cents worth.