I have an Aeris AI computer also, and recently added an inexpensive gauge set to my regulator as a backup/crosscheck to the Aeris AI. Very glad I added that piece of equipment because on my last dive trip, the computer locked up and I could not get it reset for the dive (long story having nothing to do with violations). But since I also had the SPG/Depth gauge set and my wrist watch, I went on my merry way for two very nice dives in Curacao without having to rent a regulator/gauge set.