Amps which are Great, but either Unknown or Underpriced

1) Agree on the Yamamoto A-08s. However, speaker matching is crucial. I found that it did not have enough drive for my Zu Definitions - perhaps, in part, because of very long speaker cable runs. But a steal at the price. Gorgeous to look at. Impeccably made. 
2) DejaVu 45/2a3 SET. Similar in sound and price to the Yamamoto A-08s, but aesthetically challenged.
3) Audio Refinement Complete Integrated. No longer made, but occasionally appears on A'gon - especially if you are looking for a rich sounding SS integrated at an incredible bargain (less than 4-500USD) - even as a back-up.
3) Ancient Audio - my current amplifier. Unknown, but far from underpriced (unfortunately).

Ghent Audio. Class D amplifiers that have a loyal following. I won't bore you with how much of a bargain they are cost wise, and their superior sonic performance compared to x, y, and Z. I'll just say that I use them with my Maggies to great success and they replaced such achievers as Edge Electronics, Consonance, and Antique Sound Labs...all well respected offerings. $1500/pr 400wpc sonic splendors!

Mike

I am interested in Wells Audio.

I agree with Jolida. I have the Fusion preamp.

I have a friend who owns the Audio Refinement integrated and it is indeed a fine piece.  

Parasound. and for more bucks, Ayre