I use this watch for fieldwork. The compass acts as a backup backup compass, in case I lose my proper compass and for some reason the electronic compass in my GPS fails! The altimeter will need to be calibrated whenever you want to use it, done simply by entering your current known elevation above sea level.
Titanium and plastic makes the watch nice and light
Multiple alarms are brilliant
I've only used the world time once, but it worked without a hitch
The radio controlled time is accurate and reliable here in the UK
It's built like a tank and will take a lot of abuse
The watch is pretty chunky
The watch face markings and hands aren't luminous in the dark (Casio has released an updated model with luminous painted hands)
Only 100m water resistant, my dress watch is more water resistant!
The bracelet is pretty heavy and pinched my skin/hairs. I quickly replaced it with a NATO watch strap.
Backlight only illuminates the analogue hands
If you need a watch for work outdoors, look no further. It's a little big for day-to-day use, though I'm sure some people with larger hands and wrists won't have an issue. Even though it has a backlight, I'd have much preferred it if the hands and markings were luminous too. 4 out of 5 stars, losing 1 star based on the poor backlight, lack of luminous hands, and only 100m water resistance.