how does rogue zeus compare cat or atma-sphere?

Jeff_jones, I agree with your general point that price does not equal quality, and there are many instances of that. In the case of CAT and Atma-sphere I would say that rule does not apply, they are expensive and they deliver SOTA amp performance -- which does not mean the Rogue isn't in their league, but I have not heard it.

Pubu157 - Too bad none of us has heard all 3 so we can help with the original question. In any case, no debate with your comments. To the original poster I only intended too share my experience. What I have found is that buying an amplifier is a bit analogous to buying a pool cue. At a pretty reasonable price point a good manufacturer can do everything that can be done for the sake of performance, the important thing in choosing for performance is to find the feel that suits your personal preference. Beyond a pretty reasonable price point (and you can go wayyy beyond if you wish) the purchase is about pride of ownership and exclusivity, just need to make sure that the feel of the cue remains top priority.

Optarchie, what does/would the rest of your system look like?

escalnte fremonts, hovland hp200, amr cd77 and clayton audio m-300's

I heard the Zeus driving big Maggies using a digital source I thought the sound to be very good.A few months later i heard the same speakers driven by more expensive Pass Amps using an analog front end.I thought the sound with the Pass to be better.
I dont remember the preamps used.
My amps are self heated SET's and couldn't drive the Maggies better then Pass or Rouge amps but when placed with the correct speakers I would say my 845's are better then either.
What Pubul57 asks about the rest of your system is more important then finding a giant killer.