Buying a Tube Amplifier

I have alot of audio equipment, my favorite set up is Simaudio moon W5.3 and P5.3 amp and preamp with B&W or Axiom speakers. I am listening to alot of electric guitar right now and can not imagine it sounding any better.

I have always wanted to try out tubes and I am going to. I want the first step to be something under 1K ish. I have been considering Antique sound Labs AV 25 monos.

Does anyone use or know these and can anyone give me some ideas of something that has really impressed them and what you are comparing them with?

Any help is appreciated