Square off is just a toy and quite useless, unless you're maybe some kind of collector. But even then, for the collector the DGT board is a better addition to the collection. Square Off has two problems, 1) you can't hook it up to a computer, and 2) It automatically moves the pieces. It's actually very beneficial to move the pieces yourself, because it activates the brain much more. It's the same reason why watching videos is an inferior way of learning as opposed to reading a book and using a board. It's just a too passive method of learning.
It is a kind of toy, but it has some clear advantages.
With square off you have an additional motivation to use a physical board when playing online.
How many people complaining here that they are not used to a physical board? A lot.
It has something to do with chess culture. I have also a Novag Robot Adversary, which was very expensive when released and now is a highly collectible item. The Adversary also moves the pieces for you but with a mechanical arm.
Hold out for 2 months and buy this: https://www.chess.com/forum/view/chess-equipment/dgt-is-making-a-new-dedicated-chess-computer
Should be available in July.