The medium size band is about 7 1/2 inches around your wrist, after clasped to the loosest hole (5 3/4 on tightest hole). The face is 1 1/4 diameter, which is larger than regular type watches I'm used to, but smaller than alot of "alarm" watches I've look at. Ten holes on the strap, which makes it convenient. Timex 1440 digital watch was the most attractive alarm watch I saw. Setting the alarm is fairly easy, taking about 10 seconds, and you can do it with one hand (so, while you're wearing the watch). When you are wearing the watch and the alarm goes off, it's very easy to silence the alarm (push any button), but to disable the alarm so it doesn't go off the same time the next day - that takes several steps. As long as you're ok disabling the alarm after you've taken the watch off for the day and can use two hands (or are not in a rush), it's still a big help having the alarm reminder.
I've had this same style of watch for years. I wear it until it breaks (usually by user error). I never take it off. I shower and swim with it. I say its waterproof, as long as you don't go deep sea diving with it.