The watch is a great size, is very rugged, and provides a lot of useful information.  I have been hiking and backpacking with this several times and have had no issues.

My favorite features:

Atomic time.  Never set your watch again.  I'm not sure how it works in different time zones.  I don't remember if it auto adjusted or not.  It probably says so in the manual.

Solar power.  I have owned several watches.  Nixon and swiss army are my favorites.  The batteries die so quickly, especially the Nixon, who requires you to send them the watch and $45 to replace the battery.  This casio is solar powered- awesome.  It really doesn't need much light to charge or stay charged.

Moon phase.  I use this more than I thought I would.  I don't use it in any important ways, just for fun.

I wish the light stayed on just a few seconds longer.  I think it turns off a little quickly.  I also haven't had much luck with the compass, which seems like you need to remove it from your wrist to use it, which is incredibly inconvenient.