Best amp for Sonus Faber

The best is going to be a personal decision.   But I’m not sure you’re going to do too much better than the Luxman you already have if you stick with a SS integrated. I was about to respond to your other post until seeing you purchased the III’s.  Did you by chance audition the Maxima Armator?  That’s the one I would have been looking at, lol.

I’d lean towards Audio Research or Accuphase personally. For separates I’d stick with Schitt + Class D Audio.  Just me.  

There are a lot of great amps that are highly synergistic with Sonus Faber. I owned Olympica for many years. My personal favorite is Audio Research and one of the ones most recommended. It produces a very musical and natural sound. I have heard them with many other amps. It is what you are going for Luxman produces a very shiny sound... being treble forward... Sonus Faber does a very good job of calming this down. MacIntosh produces a very heavy midrange and bass but is light on the details. If you want a sonic spectacular with holographic imaging, go for Burmeister. 

The new Audio Research I-70 will really make the emotional connection with the music. It is a really musical amp with plenty of detail and soul. Highly recommended.