Summary: I could not ever warm up to this watch. First its like wearing a grapefruit on your arm. It never took a calibration for altitude, barometer was innaccurate, paging thru the screens was annoying, and the backlight lasted too short.
Summary: This watch (at least mine) would not stay calibrated. With a steady calibrated barometric pressure reading the altimeter readings continue to fluctuate when remaining at the same altitude. Buy the basic Casio PAW40, I did.