I'm interested in DU's experience with Sonoran, though. I've heard the name but never experimented with it.
Not much to tell, really. It's just that my long-time preference ($5,750 retail Stealth Indra) were pushed surprisingly hard by the Sonoran Plateau ICs. If I hadn't already purchased the Indra, I wouldn't have paid the difference - even at my discounted beta-tester prices - over the Sonoran.
With the Indra, you get a little extra tonal 'presence', or realness, if you will; expanded soundstage (far and away the best I've heard - see Srajan's review for more on that); and a way of cleanly removing digital...I don't know...stuff...that seems to be the bane of virtually every system I've ever heard that's connected to anything that isn't spinning vinyl. Every other cable I've heard - including the Sonoran - cleans it up via some sort of masking. Some do it better than others, but with the Indra, it's simply not there...at least I can't hear it, and I believe Srajan had something to say about it as well.
If it weren't for those differences, I'd have sold the Indra in favor of the Sonoran, just on principle. I plan to keep them, though, as a hedge against any future fiscal requirements. After a week or two with the Sonoran, I doubt I'd miss the Indra all that much.
But as is the case with the Butler Monad monoblocks, I know what I have, and I'm not interested in giving it up unless forced. Just can't bring myself to do it.