My system has gone through numerous revisions before I ended up with the Sunfire Ultimate. I had a two channel McCormack DNA .5 Deluxe for amplification and used a Sonic Frontier Line 2 as the pre. I loved it for much. Very liquid, very smooth.
But my needs changed and I traded in for home theater capabilities. I ended up with a Denon 5700. In terms of capabilities, it was a step up (5 channels, dts and all the bells and whistles) but musically, it was a severe step down.
I then tried out numerous seperate combos, including a Lexican processor/pre paired to an Audio Refinement 5 Channel amp. Better but not yet there. For what it's worth, the Lexican was probably three years old and in the processor category, that made it ancient. The Audio Refinment gear reminded me of my old McCormack. Sounded good but at 125 watts per channel, lacked the headroom I like to have in reserve for dynamic passages and high decible parties.
In the end I took the plunge and upgraded to a Sunfire Ultimate Receiver. And. It. Rocks.
I really do love it. It has a totally different sound-signature than my old Tube powered Sonic Frontier; more unvarnished clarity than soothing silkiness. But other than female vocals, it's a sound that I personally prefer.
Compared to any other amp or reciever that I've owned/tested it has dynamics with ample room to spare. Even at deafening decible it never losses control or sounds at all congested. Bass is slamming, imagining is very refined.
It has all the bells and whictles you could ever hope for in a home theatre setting, including one that suprised me. In any other processor, I've always been a purist when it came to my music. I'd always bypassed and dsp processing, opting instead for as straight a path to the music and let my dac or cd player handle to processing. Just not interested in having my music tinkered with in order to sound like a concert hall or dance club.
That said, this Sunfire has a Holographic Imagined function which I have come to adore, even on two channel music. It's subtle, but it blends the two channels in a way that adds presence into a tight, virtual center channel. It makes vocals very up front and center.
"Ultimate" is hard to validate, but in my experience you'd have to spend much, much more to hear a minor improvement above and beyond what this puppy is capable of; it's the law of diminishing return, and the Sunfire hits the sweet spot.
Long reponse, but the bottom line is that I can't reccomend this unit highly enough.