I have a Simaudio 600i in one system and an Audio Research Vsi55 in another. The ARC is used in my office and helps keep me warm in the winter. All kidding aside, it's a really great sounding integrated and I don't need a lot of power in that space. I currently have my Harbeth Super HL5 Plus in the office and the Vsi55 has no problem driving them when I get the opportunity to turn up the volume. The 600i is very dynamic and detailed and mates up great with my Harbeth P3ESR speakers. It's a nearfield system in my computer room and sounds fantastic. In the right space, this would make a wonderful main system. Actually, I enjoy it as much or more as my main system, it's a little more detailed, but warm and easy to listen to.