One major limitation not mentioned here is it only does 8 ohms and above safely (according to the specs), which is one reason why I went for the unpowered rack.
My big-ass FRFR monitor is 4 ohms, like a lot of larger monitors. The new matrix FR212s are likewise 4 ohms. And if you want to stack 2 FRFR speakers eg 2 x Q12, again that's 4 ohms. So to me it really only suits players who use 1 smaller FRFR cab
OTOH many guitar stacks are 16 or 8 ohms, so that's not a bad fit for them, 2 x 16 ohm cabs would roar! I'd definitely check the cab first before cranking it that it's not 4 ohms!
From all accounts I've personally heard it does sound really good. 