anyone had a listen to the b w 803d's

They sound nice but I could name ten or so other speakers at their price points that, to me at least, sound better. The brands named above (although I've not heard the Piega). Would add Sonus F and Montana.
I think the 800 series is still made in the Uk. Other than the ten thousand dollar two way and the one that looks like a snail, B and W makes their products in China. Q

I have found Marantz to sound pretty good and be very under rated. It is hard to say because B&Ws are one of the few brands that REALLY need lots of power... You can get lots of power cheap from Rotel (very cheap used). I heard The 803D back to back on Classe' amps and rotel amps. The Classe's were a bit better but if you did not hear them back to back you may not know what you were missing.

So what would you be missing with Rotel? IMO a bit of treble refinement and a touch of bass control at higher volumes.

Also most people seem to think the Sophias are pretty easy to drive but still diverse good equipment.

Yes, a few times and they never get any better...An old line with an old sound...When it comes to B&W there are better speakers at every price point