I can confirm that the SIT-3 is a special amplifier. It took a while for me to find the right one, and in the interim I was using a FW F-8. It's pretty special too, but just in different ways. I'd say it had a little more punch and power, but didn't box your ears with it. I took a single-ended 300B based amp off line when tubes were getting hard to find back in the winter, and haven't looked back. The 300B was glorious, but the First Watt amps control my speakers better and I don't miss a much with the SIT-3. I am turning my pre up a bit more with the SIT-3, but not maxing it out. Valvet amps were always a consideration, but never found one to buy when I was looking. Would still like to try one.