2 points:
1) I could never get my 990 to do what I wanted until I got a MX-500. Now it is a joy to use. The front panel control is unusable IMHO.
2) The auto calibration doesn't work, expecially with a Sunfire sub. Just use an external SPM. Also, be careful when using the internal tones on the sub. The calibration signal isn't correct although there is some work-around (previously posted). Also, there are some setups (large fronts and 5 channel) that give double bass in the sub. It is a software bug that they are working on (and working and working...). It has been a known issue since the unit was released and we are still waiting for the upgrade.

Bottom line is, once set up correctly but without using one of the buggie modes, it sounds great. You just need to be aware that the unit has bugs and doesn't always do what you would expect or what it should.

Outlaw has told me for months that the upgrade will be done soon.