I am always afraid of longterm channel balance (right to left) with aging electrostatic panels but that might not be based in reality…. Never owned any. ML has a very small sweet spot so be ready to mess around with placement. I like them ok but have been unwilling to ever mess with them as my system does double duty in a home theater (built for two channel).
The 800D3 is probably an ok speaker. I have heard the 803d3 and it was really thin (no bass). The 802D4 had a lot more bass but maybe still not as much as the older 802D2. The 800 should fix the bass issues of the smaller models.
I found the 802D4 to make male vocals sound a touch thin. They had good bass, detailed but colored mids and detailed highs with a touch of brightness. They were $35,000 all on McIntosh gear. I came home and listened to the same songs on my Revel 228be/JL sub (subs and speakers together are $16,000 retail) McIntosh combo and I feel my system was better. Better bass, smoother more natural mids and upper mids. Soundstage is very room dependent but the revels were more stable and just as wide.
if you go B&W make sure you have a long demo with high SPL. Play some bad recordings. Make sure you can live with their aggressive tuning for “detail”.