Motion Sound is a small company, but the newer models are really quite good and well thought out. They have been responsive when I had a question.
I too like PPA speakers, and have QSC's, but for my use case I like the ease of a one box solution that is stereo-ish. And I think the MS handles piano quite well - maybe not quite up to the level of an RCF or other high end PPA, but certainly well better
than any of the legacy "keyboard amps" that many of us have used over the years. Check out Al Quinn's Youtube video where he A/B's a MS with PPA. MS has really raised the bar with these new models.
In the end it really comes down to what your tolerance for the schlep is? With two keyboards at rock shows with fast setup, PPA's and a mixer and stands doesn't make sense for me. The MS has stereo XLR outs, so very easy to put on a chair and have the sound guy plug me in and go. These keyboard amps from MS are NOT much of a compromise, if at all.