Yup, very stable, had an Extreme on an industrial 1 Ohm load, running on the bench with test equ. hooked up at 90 %...walked away (couldn't stand seeing it), came back after dinner, and there was my sweetie, still (literally) cooking. Didn't blow, didn't melt a transistor, which surprised me, but wasn't too far off doing that though as the amp was very hot......but still worked...also, we have as customers a couple of Universities, as well as industrial scientific companies and also the defense Industry (an educated guess). Reason is exactly that, stability, and more important, an insane and stable frequency response....that's my baby, but also to be realistic, it doesn't have 900 or 1000 + Watts max, as the PS is 800 +, and although the trannies are efficient, they still lose some wattage up there. However, the typical Rolls Royce approach: more than adequate.....
Now, again, ....I do understand that if your heart is set on high Wattage, some of the actual control facts might not seem that important, and honestly, I don't know if Arcticdeath or others in his situation would be 100 % happy with any amps less than ultra high Wattage....just don't want to create a situation where one party might not have a happy ending here....
Late,
Klaus