You want simple sufficient and big numbers? I totally agree the Aeris atmos II or the Oceanic Versa Pro is the way to go. Note that the Atmost II is being replaced by the XR2 which is the exact same computer with a little smaller display. But if you can get your hands on an Atmost II go for it you want regret it! I had the Versa Pro and now the XR2 simply because I loved the last one!