Maschine seems overpriced, though it is cool. Seems completely sample-based as well, so not as flexible as say, BPM. About BPM: It requires iLok, and I had Mach Five 2 for a little while and it has graphics issues on PC's. (I ended up selling it to a Mac user.) Also MOTU's tech-support is almost nonexistant...
Having said that, BPM does look sweet, in fact it looks like what I was hoping Guru 2 would be...but I'm still passing.