I'm an extremely happy owner of a Sim Audio 600i. I bought it to replace an AR tube separates setup as my family couldn't deal with a non-automated system. I listen to a wide gamut of music: Zep, Rosanne Cash, Talking Heads, Beethoven symphonic and Beethoven piano, Diana Krall and Serge Gainsbourg, for example. I should point out that my speakers have a titanium inverted dome tweeter and a ceramic driver so they're not necessarily the most mellow thing out there. No worries. The 600i is superb with them. (I've never heard your particular speaker. My first high-end speakers were a set of Apogee Stages but that was long ago and I can only remember their transparency. I used them with the AR tube setup.) Micro detail is everything you could ever want without being fatiguing. The amp is musical across the spectrum with bass being tight and powerful, though never overly so, and even the deepest bass notes discernable as different in pitch from each other. Mids are open with beautiful timbre and highs are clean but never shrill. The soundstage is good but not mindblowing as I would not call this a "forward" amp; it's a "middle" amp. I'd say the only time I miss my tube setup is in the weight or three-dimensionality they give strings in chamber music or when someone is plucking an acoustical guitar that is well-miked. Nonetheless, this amp has better pace than the tube setup - I often find tubes slow. That being said, I think the 600i is about 5K used which is more than you're planning to spend. I considered the Osiris (recommended by someone upstream) but never did audition one. I happened upon the used 600i while I was auditioning a Hegel H360 (which I hated) and it was pretty much love at first note. ModWright was also in the running though I didn't get around to auditioning it either but they're well reviewed and I like the idea of a smaller manufacturer. I'll just throw this in - and as you know there's a ton of stuff out there - but Wyred4Sound integrated are supposed to be category killers and they do offer a home trial program. Good luck.
