Steinmusic SP 1.1s for my Wavac MD 300

unless your room is small or your music has limited dynamic range, I think you will find that you will begin to hear an increase in distortion at higher volumes. SET amps begin to produce significant amounts of distortion as they go up in power output. Member Atmasphere has posted extensively on this issue and I have found his opinion on this to be correct in my own system. I think you would like the single driver sound very much at low volumes but as volume and or bass content go up power demands increase exponentially. This was readily apparent with a 300b amp on my 95 dB quasi full range speakers. 

That much power would work just fine, IMO, unless you have a huge room or want to reproduce concert level sound. 

Normie- The nominal impedance of 8 ohms is OK but the minimum of 3.2 is not ideal for a tube amp. Could not find an impedance w frequency graph to see how severe the curve is or what frequency the minimum is at, or if the published sensitivity is realistic.  I found that 30-40 WPC tube amps could drive my 89 DB Merlins just fine, but they had a very flat impedance curve @ 6 ohm nominal.  Maybe AudioMirror offers a return policy?  Be aware that the 6C33C tubes run VERY HOT.  Great sound but VERY VERY HOT.  I would not use them around young children or in a hot climate unless you have cheap power and good A/C.