As many women are rightly concerned about the feeling of thongs (a.k.a. the wedgie), when shopping, look for the thinnest fabric available.
High-pressure activity, like going down a water slide, is the source of many a painful and exposing wedgie, for both men and women.
Anything that resides in the middle of your backside must be the equivalent of receiving a wedgie.
They'll go with nearly any type of shoe from a wedgie sandal to a flip-flop or flats.
The butt of the suit will shift slightly, but if the entire swimsuit becomes a wedgie it is not a good fit for you, and you will spend the entire day pulling and tugging at it.
If your pants are too short, you run the risk of getting a wedgie in the back, or having the straps come up too short on the body without room for adjustment.
If you have a long torso, you can purchase your top and bottom separately, allowing you to find a suit that covers you up and doesn't give you a wedgie.
They shouldn't give you a wedgie, they shouldn't bind or chafe, and you should feel sexy in them like you would feel in any other pair of denim pants for daytime.