I already have a dive computer, but I am becoming an instructor and am required to have a back up watch that counts seconds. I want something cheap and simple (simple like: tells time w/ seconds, maybe a stopwatch, alarm, or light). I have been looking at some models by Freestyle, Casio, and Timex. Does anyone have any suggestions of a digital watch that is under $75 (closer to $50 would be better) that is rated to 100m or 200m? I would prefer 200m since most watch companies don't actually suggest taking a 100M water resistant watch diving, but if people have tried it and say that it will last underwater then I will consider a 100M water resistant watch. Could really use some advice on this. Thanks.