A friend of mine is selling a Simaudio Moon. I heard it and was quite surprised by its sound quality. Knowing of the Sim Audio Products, I was not particularly surprised in the sense that it was high quality, just the magnitude of its clarity and poise, with great bass extension, as well as soundstaging. He demo'ed it to me on a pair of Tylers, quite good, then the Merlin, top speaker, and it was very good. Not good for the price, but good. I recommend it highly. It does not give false euphonic colors, but great control. The B&W's are a little 'friendly' in the bass, and this amp can help control them very well. He has the product, I think listed now, though it may be gone by now.
Anyway, at about 1150. it makes for a steal of a product. Any of the moon products are quite good. Tubes will be too soft and euphonic for MY taste. Also the Jolida, if you are into tubes, makes very good product, worth checking into. They also make hybrid, tube/solid combo pieces.
Good luck in your search.
Larry