@OP. There are other USA made affordable tube amps to consider such as Rogue audio. Despite your loudspeakers' relative efficiency, you might want more than forty watts per channel in your quite large room. SETs definitely need not apply unless all you want to listen to is harmonic distortion.
Is all the hype warranted
I've been seeing alot of glowing reviews of Decware amps over the last couple days. Particularly their Zen Torii and ZMA amps. Andrew Robinson, Steve Gutenburg, Harley Longrove and Jay are all gushing about Decware. For those tube guys out there, is Decware that good? Is the hype warranted?