First, there's no mention of Nitrox anywhere (except in a screenshot). Most of the serious folks use this mix (basically, air enriched with some more oxygen) for their dives, it's unclear if — or to what extent — this supports Nitrox.
Second, there's no mention of the decompression algorithm they use. Buhlmann, Suunto RGBM, VPM are examples of algorithms where the assumptions about human physiology are backed by hundreds of thousands of dives, but what is driving this specific piece is kind of a mystery. As this device comes under "life support equipment" category, I would love to see more information about that.
Third, battery life is a concern here, while it almost never is with dedicated dive computers. My main device requires a trip to Switzerland every 10-15 years, and my backup device is serviced locally every 3 years or so; having a "two full days battery life" somewhat pales in comparison.
Finally, $10 a month is pretty expensive, especially when it comes on top of $700 down payment. Unclear what happens when you stop paying. I don't doubt that there are people who don't worry about that kind of money: the watch blogs are full with people discussing diving with their Rolexes and Omegas, but I have never seen anyone doing that in real world. 90% of the people use dive computers (owned or rented), and 90% of the rest use basic G-Shocks; you are lucky to see anyone with a mechanical timepiece (which almost always happens to be made by Seiko).