Altimeters are great, they can be very accurate but being barometric you have to calibrate them and they will only give reliable data if the atmospheric pressure is not climbing or falling rapidly. The only way around that is to combine a barometer with a gps like some garmins, gps does not give very accurate elevation data but when combined with a barometer gives the accuracy of a barometric altimeter whilst compensating for changes in pressure and self calibrating.
I wouldnot wright them off as it also gives you a way of predicting the weather and showing everybody at work! I vote G-Shock, I love them and you can get great deals on them, I wouldn't pay rrp look on amazon, but compass models are more expensive. Again be wary of a compass on a watch, it will only give you n, e, s, w which you can get by other means and isnt much use for map navigation.