what are the best sounding Accuphase or Luxman amps/preamps?

For example C-2450 + A48, or C-10x + M-10x etc

The best sounding components are their top-of-the-line models. :-)

I was going to say the "most expensive ones" but  @yingtonggao said it first. I would think that these companies don't screw up the pricing.

Yet, the F40 was faster than the F50, so anything can happen....

Most Expensive, Nonsense,

Are you only considering Solid State, or Tube Models?

Tubes, the better question is, what tubes sound great 'to you' because it's not better, rather 'preferred'.

My Luxman 10 wpc tube amp is terrific for efficient speakers in a small space. It would be nearly criminal to put a more powerful/more expensive/most expensive amp in here. 

The object was to be able to use tubes in my office, low power to minimize heat, size, increase placement options, and lower cost compared to more powerful category. Achieved!

here it is now

Never heard an Accuphase except in a showroom.