Likewise at my home DZ. There are a few, myself included, that jump with an Altitrack. None use the JumpTrack software. We've done some comparisons after dives (including the standard ProTrack users) and the data is amazingly consistent between us all.
Doug, funny you mention the strange reading... I did a 3K hop-n-pop this past weekend and the Altitrack recorded the jump as 13K+? However, during exit, face read 3K. First "anomaly" in 125+ jumps. Don't be sexist… Broads hate that.