I am looking at getting a new gps unit and wanted to know if anyone has used the Garmin Vista (or Legend) HCx. I see the Alaska chip is about $80 and that is convenient. But the altimeter/barometer is what I am most curious about. Is it a worthwhile feature. Reason I ask is that I read in a review of the unit that the alitmeter had to be calibrated. If you don't know the sea level, that would be useless. Or am I reading into things to much. Is the calibration an automatic operation. Any insights on the Garmin Vista or Legend HCx. Or for that matter, on the Garmin Alaska sd chip? Thanks for any thoughts.