Best Integrated Amp? Help...

Haven't tried it with B&W but the Bel Canto eVo2i is a very nice integrated. I have used it with a few different speakers always with excellent results. Runs cool and quiet.

The Krell KAV-400xi is in your price range, and worked very well for me, when I had my B&W N804s & N803s. This is a nice sounding and powerful (400-wpc>4-ohms) Integrated Amp., with excellent bass extension. It was in my B&W System for a few years, along with the Krell SACD Standard, which made for a great, inexpensive, and nice looking 2-box system. I had to spend 3X the cash to improve on this Int. Amp.

Maybe try the Krell 400xi.
Lots of power and sounds great.

Musical Fidelity A5 - used
Shanling A-3000 - new
Cayin A-88T Vacuum Tube Integrated/Power Amp - new ("only" 45 W, but you will be surprised)
Vincent Audio - SV-236 Hybrid - new

Primare i30 - used if you can find one for under 2 grand

Bel Canto is interesting, but if the Rowland didn't do it for you, I am a bit skeptical this one will either - again buy used if you can find one

I will second the Shanling A3000.