My 305 died while mountain biking in CO. My new 910 will be here tomorrow.

Has anyone actually done a race with theirs? I read a review on Amazon in which the guy says he lost his on the swim. Maybe I've been really lucky, but I have yet to have the rough swim where I get kicked or pummeled in any way. Could be my strategy of just staying away from everyone! Anyway... I'd hate to have it come off my wrist and sink to the bottom.

Veronica