I have one and among its attributes the one I find most noteworthy is the toadstool like palm rests. It is a very clever design, is fully adjustable and works very well.
The adjustable tenting feature is nice and operates well but lacks the firmness a fixed unit would have. As well as folding flat, the adjustable tent would be good as one gradually gets use to greater angles and of course to find their ideal angle.
As kittykatmax noted in an earlier review, another unique feature is the dual action space bars. A nice feature when typing at more acute angles because of the changing thumb orientation.