I don't think the "sounding a little more powerful" affects girl with guitar. I hear it on big classical.
I think the Italians are a bit more transparent, a bit more resolving, a bit more extended in the treble. I think I hear on solo vocals something that I want to call slightly greater "purity." Is this the PSET versus push-pull? But I would not bet money on this, because I may just be getting entranced from looking at those DHTs.
The Italians sound more "professional," more like "big boy" amps -- although I appreciate that it's hard to know what I mean by that.
At this stage of break in the Frenchies have a warmer tonal balance, and sound fuller overall. But this is the raison d'être of Jadis -- the musicality and the sonic charm. I don't expect the Italians ever to catch up to even on those particular sonic parameters.
In summary, on girl with guitar, the Italians do a slightly better job of making me believe that there's somebody live singing to me in my room. At the end of the day that is my sole voting issue. Despite the present edginess/brightness issue (which is completely absent with Jadis) presently something is pulling on me to keep the Italians.
For the record, the favorite iteration of the system so far of Don and of and of David Blumenstein and of Jim Yager and of Pat and of Pat's girlfriend had Jadis driving the midrange/tweeter.
I think the aesthetic design of the amp is beautiful (as audio components go). It still puzzles me why this is the only 845 x 4 PSET in the world.