The amp for you is the Eastern Electric Minimax - I know, 'cause I was (until last week) driving a pair of Royd Doublets (89dB, 6 ohm) with this genuine bargain pre-power. I've moved up around twenty rungs on the speaker ladder in the last week, but no way would I get rid of the Minimax. My personal favourite sound I've yet heard, and I've heard 552/500-based systems, big Dynavectors, Border Patrols, DNM, my own foray via Naim 52/SC/250, etc. etc.
What I'd say is that it just does exactly what a high end amp should do, but at a really affordable price. I'd be unlikely to go back to SS, though it's feasible I might add a second Minimax power amp to bi-amp my Avanti IIIs.
My history is I went: DNM->Naim 82/HC/250->52/SC/250->Nait2(modded)->MiniMax
...the DNM was the most musically engaging in many ways, but the amps are fragile and ergonomically disastrous. The 82/HI was a big disappointment, and didn't last long before being replaced with a 52/SC. This did all that Naim is meant to do, but cost a small fortune, and in the end I found that (with efficient speakers) the modded Nait 2 I have did things 95%+ as well as the big Naim outfit. The first system to convince me to move from the Nait was the Minimax. Cracking amps, miles better than the 52/SC/250 (though not as powerful it must be said) and MUCH cheaper. Roll a few NOS valves in there, feed it a top-notch source and you've an amazingly capable, very fast, dynamic, musical and insightful amp.