First off, Al's comments are very informative and much appreciated. Secondly, I only comprehend Al's comments at a layman's understanding.
So, with that in mind, I have heard the Sabrina's twice. And both times I was pretty enraptured. The first time was with D'Agostino mono blocks and preamp with a Bricasti M1 DAC. Not sure of wire and other ancillary items, but this absolutely hit the nail on the head for me. This was at The Show Newport 2015. My friend and I both thought it was a very lovely sound. Certainly in the best five or six rooms.
I also more recently heard the Sabrina's with an ARC GSi75 integrated amp. So, different room and supporting cast, but again, wow, what a nice full rich sound. Tube magic in evidence. The ARC has its own DAC, which I think they used, and this was a very nice complement for the Sabrina's. For only 75 wpc, these tube amps had an iron grip on the bass and I was pretty astonished as were others as well. I heard them at at a high end get together and there were a number of people who felt this was one of the best setups in the room; there were 6 or 7 total and they were nearly all Wilson with ARC gear. This particular Sabrina/ARC GSi75 integrated pairing also one of the least expensive at that get together.
I still think a lot about the Sabrina's with an ARC GSi75 integrated or the D'Agostino gear. Very nice indeed. My one caveat concerning the Sabrina's with an ARC GSi75 integrated is that the amp takes 45 seconds to power on and since my system is used with TV/Movies as well, that'd be a no go as my wife would not accept that. Never hurts to dream though.
BTW, most of the time I have seen the Wilson line displayed they were being paired with ARC gear. I have heard most of the floor standing line and I thought the Sabrina/ARC GSi75 integrated was near the best. On that same day I heard the Alexandria XLF with D'Agostino mono' and pre and it was very engaging but to me the cost differential seemed unjustified. Of course, this is just my own opinion. Good luck in your journey, hope it is a lot of fun for you.