BW 801 D4 or BW 802 D4 + 2 subs

801D4....Also, the McIntosh has plenty of power to drive them. You can always add subs later if you are not happy with the bass output. I had a pair of 802D3s and powered them with a Naim Uniti Star in a large room. The bass was adequate but then moved to a CODA 16. The presentation was much better albeit at a significant cost. I was amazed at what the Naim did though in that large of a room. 

Subs always subs. electronic music can only be played properly with subs…. Not kidding. 
 

Anyway, I listened to the 802D4 on McIntosh Mac611 mono blocks and McIntosh 2700 tube preamp. It was ok, the bass was fine, no major complaints, mids were a touch thin (tipped up a bit). Then I came home and listened immediately the same songs on my Revel 228be, McIntosh MC462, with two JL E112 subs highpassed at 60hz. Honestly my much cheaper system was better, much better. The bass was well beyond the depth, quality and slam the 802d4 without subs could not touch. I also think the Revel are more natural/smooth sounding but they do give up some detail next to the 802D4. I would expect the 801D4 to come up short next to subs too. 

The capacitors in the 801 are a bit better still and sound a bit cleaner 

if you can afford them. My dealer Perrotta consulting  carryB&W and give excellent service as well as pricing plenty of low bass.

Personally 801. I much prefer completely coherent sound across the spectrum. B&W has put a huge amount of effort into making these things the best they can… flat to 15hz. Why add subs to the mix when they are unnecessary. 
 

Also, from the  aesthetic point of view, single towers are much more elegant. I remember finally getting rid of my subs… both from an aesthetic and sonic perspective… a much cleaner and more elegant solution!