@lcherepkai 45 watts is a lot of power for an SET! Its very difficult to get good bandwidth in an SET with that sort of power, but its pretty easy with a more conventional Push-pull amplifier, and the power tubes are often much less expensive! Our M-60 makes about 60 watts into 8 ohms, but the power tubes for both channels together are only $420.00 and we warrant them for a year. If you had a H/K Citation 2 (refurbished) they make 60 watts also, and the output tubes are only about $140.00 total. That amp is also wider bandwidth than almost any SET, and its certainly lower distortion.
My point here is there are a lot of tube amps out there that may well do the job that could make more power, less heat and less distortion, and very likely sound better at the same time with a lower output tube cost. One limitation nearly all SETs face is that if you really want to hear what they are about, they should be played on a speaker that does not require that they go over about 20% of full power. This is to prevent the higher ordered harmonics from showing up- those harmonics will cause the amp to sound 'dynamic' and they will also cause it to sound 'loud'. With most push-pull amps, the usable power is much greater- often well over 90%, so you get a lot more usable amplifier power for your investment.