Just listened to the demo. Been awhile since a really unusual piano has come along. Only one string per key (and only 64 keys), no sound board or case, so it's got a sound that's sometimes more reminiscent of a guitar or a toy piano than a conventional piano.
Keep in mind as you listen to the demos that they are all made with multiple instances (up to 8) of the instrument, making it fatter than it really is. Two of the sample layers are "prepared", meaning they stuck things like leather and silk between the hammers and strings. You also get more options than a typical piano library, such as a reverse effect, flageolet (a clarinet-like woodwind instrument), compression and transient control.
An interesting curiosity, for sure. Would I spend $149 on it? Not likely.