SP Tech Revelation III - how good?

I've previously had a thread about speakers to replace Kharma 3.2 FEs in a 5,000 cubic ft room, but it has died with my last question, viz, what about the SP Tech Revelation. Could anyone who has heard/owned these speakers please tell me (1) Can they fill this space, placed close to the rear wall of a 23 X 17 X 15 ft space? (2) Has anybody driven them with a tube amp (A-S 2.2 220 WPC)? (3) All the hype has been about the bass they deliver - how are the midrange and HFs? (4) Are they in the same league as Vandersteen 5a, LS 9 arrays, Zu Definition 2s and Coincident True Reference? I know they're not ideal loads for OTLs, being 4 ohms, dipping to 3.3, so ignore that part - that's why I asked about tube amps, but dont want to re-do the long discussion that tube amps prefer 8 ohms. Thanks for your time.