I got a similar deal on my Belkin a couple years ago: an MSRP of $600 (which I think is excessive, even though it is a nice piece) and I got it for around $150.

The APC will have a trigger connection, so you should be able to plug your amp(s) into the amp outlets with a delay in place, connect a trigger cable between the processor and the APC (both the 990 and the Integra have this), and when the processor turns on it will send a signal to the power conditioner that will turn the amp on a few seconds later. Should work nicely - this is what I'm doing with my Belkin and my amps.