I just use an XM Bicep Coil. If you have been using wrist coils throughout your years riding, then it will seem a little awkward/annoying your first time. But once you get used to it, you wont even notice that its on your arm. Ive been using the same one for 4 years and have never had a problem.
have always despised leashes while sponging. did the ankle trick for years and years until eventually i got sick of that and started just not using one. took awhile when drop-kneeing, but eventually learned to never let the board go (used a scissor method with my legs and would keep one hand on the board at all times). and if per chance i did loose it, it only gives me some added exercise and the opportunity to do some bodysurfing. but getting older now, i do keep a plug in my boards and use a quick connect set up with a bicep when the surf is further out than i'd care to swim.