I respect people who wait until marriage because I could never do that. I'd be so pissed if I dated someone for years and then married them only to find out they're not into nipple clamps as much as I am. The horror.
Yickle, if you're both into nipple clamps, than you're likely to get tangled nipple clamps during time of silly faces. You need to find someone that is either not into said devices, or not into eye to eye contact. Personally, I used to like the eye to eye contact.
Never forget that said clamps are pretty tame compared to what is out there, something leave scars, you really need to watch out for those that would leave scars.