In reply to Gaz22:
I've been wondering about altimeters and GPS functions. The thing with the Suunto watches that have GPS as well is that the watches are apparently self calibrating, inasmuch as when the GPS is picked up at a certain spot height, then that height will be taken as the altimeter reading(as I understand it).
I do not know if it would be sensible to get a separate altimeter and a box conformation GPS.The latter would have the possibility of carrying a map onscreen then, rather than just GPS coordinates. Having said that I generally have managed with map and compass.(It just might be faster using GPS to find where you are in really foul conditions)
Rob