The G-Shock is a great bang-for-the-buck watch. My biggest problem with it is the oversize dimensions. It's a bit like a hocky puck on a wrist strap. That's fine if you are built like a linebacker, but most women (being of smaller stature) might find the G-shocks a bit too much arm jewelry. Recently I passed by a watch display in a store and is does look like Casio does make one version of the G-shock that is more moderate in size. Unless your wife is built for the NFL, this might be a better option.
I'm not too impressed with the Timex expedition watch. I bought one for my son and the back lighting went to crap with little abuse.
Good luck, TR