Well, I finally had an opportunity to take the plunge and acquire a second 800r for the full dual mono setup. In fairness, I didn't honestly expect a remarkable difference. But given my love for the this amp, I felt that I had to have the opportunity to try it out. These are my very brief observation after spending a week with the dual setup...
*imaging and separation are notably improved, which I wasn't expecting.
*sub bass slams better.
*mids are more fleshed out and natural.
*can now drive orthos to their true potential.
*I expected "too much" and difficult to control volume. Not at all. I still have plenty of play with the pot.
After using the dual mono setup for a week. It would be very difficult to go back. I just love the sound I'm getting from this setup. Before taking the plunge, I thought it was a little gimmicky and I was irritated with Questyle for not making this a balanced amp from the beginning. But now that I've experienced the effect of the design, I can truly appreciate their effort. Oh, and the bling factor ain't bad either.