Audio Research VT80SE amp vs Prima Luna EVO 400 or 300

Interesting thread. I am thinking that since the OP owns the same speakers as I do, that the answer to his question is going to be highly dependent on the rest of his gear-- and his room.
While IMO the GH’s can sound warm...they are actually not really a ’warm’ speaker. The GH’s, at least IMHO, are so revealing that if you place ’warm’ sounding gear upstream, along with cabling that enhances that...yes, you will get a very warm presentation. OTOH, if you place more revealing and ’neutral’ gear upstream, and cable for that, then you will get a ’neutral’ sound out of the GH’s. The synergy with the GH’s..and the room/gear, is the decider here. Personally, the amp question is a no-brainer to me...and the answer is the ARC.

Thanks jrw,

My experience has been exactly as yours. 
I had intended to go ref 160s from my ref 75, but found the sound different - as you say. Better in some ways, but at the same time another step in the direction I experienced going from Ref110 to Ref75 (I still miss the low level late night listening on the ref110 - tubey magic).

Anyway, my thought, that you have helped validate, is perhaps PS should consider a lightly used ref75 for similar money to the VT80? I think if you do you won’t be disappointed and you will always be able to move it on and get good money back.

I regret selling mine, they are very special.

ARC better sound better made in USA.

Thanks to DaveyF for weighing in.  His description of the Guarnieri Homage speakers is accurate and much better articulated than mine. 

At this point, I'm leaning toward Audio Research- there are some obvious and other reasons.
  @flame, thanks for your suggestion re: the ref75. Oh, good, more homework for me!  I rarely change quality components so this is a fun adventure.

@jrw1971 - great comments on the ARC Ref 6SE, Ref 75SE and the new Ref 160S. 

I just upgraded my Ref 6 linestage to the SE version.  And my Ref CD-8 to the Ref CD-9 SE version.  Agree 100% that new ARC gear has a significant break-in period.  I'd say 100 hours just to begin to appreciate the gear.  Although I have read comments from some who say that it takes 600 hours for complete break-in, ... I am not sure there is a lot of significant incremental improvements after 200 hours.

My reactions and impressions about the Ref 6 SE and Ref CD-9 SE as compared to the Ref 6 and REF CD-8, .... in a word:  gobsmacked.

jrw1971, .... I find your comments about the Ref 75SE and Ref 160S interesting.  I am sure that ARC and many others would say that the Ref 160S is in another league as compared to its predecessor, the Ref 150 SE. I gather from your posts that the differences between the Ref 75 SE and the Ref 160S are more nuanced.  I own the Ref 150 SE and think it is a stunner.  The KT-150 tubes and other SE changes pushed the old Ref 150 "into another league" ... IMO.  Haven't  heard the new Ref 160S or M mono-blocks, so I really have no comments there.  

But if the OP finds our collective comments helpful, ... in summary, I can't say enough good things about my ARC gear.  I never head Prima Luna gear, but I am sure it is quality stuff.  So, ... sorry, ... I can't help you make a judgment between ARC and PL.

OP, ... good luck with whatever you decide.  I advise that if you are biased (that's a pun) in favor of ARC, try to pick up the Ref 150 SE or the Ref 75 SE (the Ref 150 SE's little bro), even if pre-owned.  Wonderful instruments. 

BIF