He however, is squarely in the SET camp and suggested Quests given my price range and need for a dedicated power amp.
@scottya118 SETs have this way of more and more limited bandwidth as you increase power. Usually this means 7-8 Watts (usually via a 300b) is as much power as you can get and still call it 'hifi'. Since output transformer bandwidth falls off with power (its not the tube's fault!) usually its the bass octave that suffers as bass response is usually the hardest to get when designing an output transformer.
That is why I recommended a push-pull amplifier! A 20 Watt or even a 60 Watt PP amp will have wider bandwidth (for example the H/K Citation 2 has bandwidth past 100KHz) and will have much lower distortion.
To give you an idea of the latter, a typical SET is 10% distortion at full power (which is why you usually don't want to run them past about 20% of full power...). A PP amp might be 1%. BUT- and this is a big one- the distortion of the PP amp is considerably lower at the power level that an SET makes at full power! Depending on the amp, by a couple of orders of magnitude.
Distortion obscures detail plain and simple. With a good PP amp its no problem making out detail in the rear of the sound stage that you can't with the best SETs.
I know Vu, we've shown at audio shows in the past and he's a good guy, but in this case I think he's giving you bad advice: your room is a bit on the large side- and the Audio Note speakers are not as efficient as they claim IMO. That's why I recommend a bit more power than will be practical with an SET.