My 990 is paired with a NAD T973 (7X140W) driving a system of mostly Axiom speakers (6.1 setup with two center channels). I am very happy with the sound/setup. In my case the balanced connection to the subwoofer was probably worth the price of the 990 in itself for the noise and hum it eliminated.
The T973 seems to be a little out of favor because it has three fans that are fairly loud, but that is good for me because the noise is behind a wall and inaudible (all of my equipment that doesn't need to be exposed is behind a wall).