Audio Research VT80SE amp vs Prima Luna EVO 400 or 300

OP — I went from a Prima Luna HP Dialogue Premium integrated to an ARC 160S amp and REF 6SE preamp.  Never regretted that.  I concede it’s not a fair comparison to start with, but I still use my PL in another room and I’ve obviously made my own mental comparisons (room differences and associated equipment, again, make it an unfair comparison).  Subject to all those caveats: I prefer the ARC house sound.  Clear, liquid, bloomy, transparent, just the right dose of fleshiness.  Not even remotely syrupy or rolled off.  In fact I hesitate to even put those words in the same paragraph as “ARC.” Grip and authority might only be a B+ to a bunch of A+ attributes, but those weren’t high points for the PL, either.  When I went from an earlier tube integrated to the PL, the PL seemed awfully neutral for a tube amp.  A smidge chilly.  Sometimes not the kind of neutral I wanted.  Sometimes fantastic.  But in a battle between my mood and the amp, my mood always won.  So I tried SS for a year (BHK monos with BHK pre — yes, yes, I know they have tubes on the input stage, but that’s not relevant here).  Popped the PL back in and remembered that it does create that dimensionality-plus, levitating sound you only get from tubes.  Intent on a return to tubes, ARC entered my scene and I was smitten.  Fell hard for that sound and added a REF40 / REF75SE / Harbeth 30.2 system in my office.  ARC stuff can win over my ears even when they’re in a bad mood.  That was 18 months ago, so time may change my views.  YMMV.  

How do you find the newer ref 6se / 160s compare to ref 40 / 75se ?

I agree with @jjss49 about the sound signatures of both amps.

One thing to consider is the VT80 SE comes with KT150 power tubes, the PL with EL34’s. The PL can also use KT150’s with the flick of a switch.
Using KT150 change the PL from romantic to more dynamic with more bass and treble extension.
That is my experience with the PL Dialogue Premium HP (basically same as Evo 400 minus the balanced connections). Don’t get me wrong the PL DP HP is dynamic, holographic and has great bass and treble extension, there is just more of it with KT150.
The PL will allow you to experiment with several power tubes:
EL34 (and it’s equivalents), KT77, KT88, KT120, KT150.

The AR can use KT120 or KT150

Both the AR and the PL feature auto bias for the power tubes.

Maybe the flexibility of having the option to use several different model power tubes is important to you.
Maybe point to point wiring instead circuit boards is more important to you, as the PL features.
PL also runs the power tubes easier for longer life.

Either way, two great choices.
I would consider what the speakers sound signature is and chose the amp that compliments them.

Ex. Accurate with metal dome or diamond tweeters pick the PL.
Warmer, slightly rolled off sounding
go with the AR.

Thanks to all for your helpful posts.

@rushfan, both my golden-eared wife and I are partial to "warm." Hence our fondness for the vintage Sonus Faber GH speakers, although I’d never characterize the sound as "syrupy."
@5751That "hum" issue is a concern. I’ve had to deal with that in the past and it can be maddening. Have you tried a cheater plug on the amp power cord?

I test drove the PL dialogue premium against the Evo 400. There is clear sonic improvement, specifically in the detail and transparency.

How much will close the gap to the ARC gear?
Only one way to find out. As a brand, ARC is better. But the PL sounds meaty and ballsy like nothing I've heard before. Euphonic is the perfect word.

It is dead reliable. Every potential pain point in owning tubes is slain. Personally, I prefer detail to warmth...but what I'm stuck with is pretty damn good.

I have the Evo 400 power amp fed by a Don Sachs Model 2. Great combo.