I've never heard of this company... are they any good? They're demanding quite a premium at $90 (regular). Even $55 for a mouse is quite large, IMO.
It uses the Avago ADNS-9800 sensor and nice Omron switches. It seems like they've pretty much worked out all the kinks that that sensor has had in the past (acceleration mainly). Like I said earlier, I absolutely love my Naos 5000 and it has solid build quality. If you have a medium sized hand and palm grip, it's pretty much a perfect mouse. I have a larger hand and it's almost perfect for me.
Several of the mice nerds at OCN love it. I haven't seen any comments at ESR, but they'll probably find some asinine issue with it.