Anyone have them? How flexible/hard is the plastic? Can they be trimmed? Do they hit the gums at the top of the teeth? Have any of you that have them tried eating with them still on? I have been debating with the dentist about whether there are new applications for issues unrelated to straightening teeth. For example, everything I eat ends up wedged into every nook and cranny in/around my teeth. I would like to snap these braces on before a meal and remove after a meal-feasible?