You probably already purchased your computer, but I have owned and used many dive computers mentioned above with over 40 years of diving and as a multi-agency rated instructor. The Garmin Descent Mk2i has an amazingly stupid design flaw. It BEEPS every five (5) seconds so loud that you can't miss it. After speaking with Garmin tech support, their response is: Its to support their multi-diver tracking of air using SONAR instead of the normal techniques to transmit a signal to the computer." Amazingly poor response for a $1500.00 dive/smart watch. I am NOW in the process of complaining to their engineering department wondering which bonehead thought this was a good idea to BEEP underwater, during a dive, every friggin 5 seconds right behind my ear (transmitter must be in an upright position for line of sight to the transmitter (per instructions!). After spending the money on it, I will not recommend this to any student until this is fixed. The Shearwater provides much of what you seek, however, I would also add in, Oceanic Pro Plus 4, air integrated with compass. It is a console but has MASSIVE fonts in their lettering, and its VERY easy to use (intuitive UI) screen. The Pro plus X has a color screen, but my 4 does everything I need. I would also add that Mares "Genius" is also excellent with full color screen and big letters, but I don't find it as intuitive as my Oceanic.