I have a GPSMap 60Cx - that's the same model without the compass and altimeter. I don't miss them. The GPS gives approximate altitude and I don't see much personal benefit from adding an air-pressure estimate even if it is more accurate. As for the electronic compass, I reckon if you need a hand-held GPS then you also need a map and conventional compass as backup, in which case you don't really need another compass in the GPS. Especially not one that will fail if the GPS batteries go flat, and one that itself takes power causing them to go flat even sooner.

As I recall, it was quite a bit cheaper not to have those extra sensors. There's a temptation with survival gear to spend the maximum "just in case", but on this occasion consider carefully whether to put the money towards something else (like a PLB).

The colour display, on the other hand, is worth getting - the maps really work better with it. If you get one, check the Garmin website for software updates.