the PX 600.2 amp puts out 180w rms x 2 into 4 ohmand 290w rms x 2 into 2 ohm
with a single PX 600.2 each set would receive
145w rms per set and because of the lower
ohm load (2 ohm) the signal to noise ratio will
also be lower
with a PX 600.2 amp per set of components each
set will get 180w rms x 2 at 4 ohm with the highest
signal to noise ratio possible...
the damping factor of the PX 600.2 amp is also higher
at a 4 ohm load than it would be at a 2 ohm load
(better mid bass control)
bottom line each channel will get more power and
slightly better sound quality