I'm currently running a 990 and am totally pleased with it's performance. The 997 will probably be great, but the controling word there is prabably. It doesn't use the same DACs as the 990 and will , therefore, sound diferent. Worse ? Better ? As good ? who knows ?
The 990 is something of a classic , I couldn't ask for a better processor at the price. Or for that matter, at twice the price. If your concerned about processinmg new formats , that can be done in the disc player. Can the 997 do a better job ? Who knows.
I've been tempted by the 997's equalization as I have a very strangely shaped room for my HT set-up , but the 990 sounds so good that I'm confident that any potential improvement would be marginal.
I guess my point is that the 990 is one of the all time great pre/pros. Outlaw is making the 997 so I'm sure it will be of very high quality, but I really doubt that it's going to be a huge improvement over the 990. How much can you do for $1400 ?