I can remember looking at this amp and thinking it looked good, but if you don't know how to bias valves, be sure to buy one with with an easy to do option, ie poking the multi-meter probes into holes on the top plate, easier than my amp whereby the base has to be taken off and then you have to know where the contact points are.
Well it's a new project. I have a few FOO parts knocking around the workshop so it might be fun to see if these things make an improvement. Should be a giggle seeing these little things trying to power a pair of 15" monitor golds.
back of envelope calculation you'll get about 83db for 1 watt sat 4 metres from the speakers. At 10 watts that will give about 10 dB of dynamic range i.e about half of what is the minimum requirement for music with a lot of dynamic range like full orchestra. For most other music will probably be fine.
But the Tannoy also have a minimum impedance of 5 ohms and that might give some FR variation from flat with the SE amps, bass might be weak or even MIA, top end might sound a bit dull. But you never really know until you try it.