cost no object integrated amps

I have experience at home with the Vitus SIA-025 and the Vitus SIA-030 as well as numerous separate pre/power combos.  At shows I have heard the T&A and ch precision. 
My view is that the Vitus SIA-030 is a phenomenal amp, better than anything I have ever heard. The SIA-025 also gives a lot for what is a very small box, but the 030 is on another level of amplifier. The pre-amp section of the 030 is exceptional.  It is always difficult to describe what it is that makes it sound so much better.  I’ll try: of all the high-end amps I have heard it is by far the most 'musical', the least 'hi-fi', and perhaps, to use an overused phrase, the most 'analogue'.  All amps at this level will offer great control and dynamics but I find the Vitus offers that extra elusive, magical, 'thing'.  The musical image is very holographic too.  I cannot recommend it highly enough. 

Re your question.   I know what you mean re Luxman and a warm sound.  I directly compared a cheaper Vitus with a 2-box Luxman here: https://pinkfishmedia.net/forum/threads/a-review-of-some-amps-on-home-demo-naim-v-luxman-v-devialet-...

The SIA-30 is not warm sounding. In that respect it is neutral.  I would not call it clinical either.  It has tremendous air and separation and a very controlled and extended bass.  The SIA-025 by Vitus is a warmer amp with a softer top-end, the SIA-030 meanwhile throws out a precise treble with a very clean sound.  The leading edges are not over-represented, like in the sound of Naim amplification, but they are presented more naturally which helps make the amp more musical sounding to my ears.  Dynamics on the 30 are strong with a fabulous speed of dynamic expression from the blackest quiet to the loudest notes.   Again this is in another class from others I’ve heard.  
Interestingly the amp has 2 class settings and also a 'rock' setting and a 'classic' setting.  Whilst I tend to keep mine in 'classic' the rock setting does give a slightly more upfront presentation which suits that genre, a bit more PRaT with very fast transients.   'Classic' has more air and grace.   It’s a subtle difference though.    The class A setting is preferred for me most of the time, but I do listen in class AB at times as I find compressed modern pop sounds better in AB.  It takes a good 20 mins for Class A to work its magic though, as I leave mine in AB mode and it’s not an instant switchover. 
Good luck in your search.