I've now heard the D40R's with the Ayre K-5xe / V-5xe combo and that was very nice. Very full, neutral, slightly warm sound.
I can see how people are calling Ayre "tubby".
It was missing a touch of lively, pacing (a little soft) for that sort of connection but would overall beat many others.
Hopefully I'll be demoing the new AX-5 and VX-5 soon.
I'm looking into Plinius 103 (don't think I can demo this), Pass labs (not narrowed down a model, hopefully can demo)
I should be able to demo a VTL and Electrocompaniet soon.
I was looking at the Quicksilver V4 but can't demo it. I'll have a better idea of tube after the VTL.
I first heard the D40R's with a 300wpc class A and was blown away in clarity and pacing but missing just a touch of fullness.
From what I've heard so far these speakers "can" sound very nice with good clean lower power but "can" really shine with more.