I have a pair of the B&W 805D3 speakers.
Have paired my B&W's with two different integrated amps: McIntosh MA252 and Raven Osprey. Currently using a Pass Labs XA30.8 (with both Conrad Johnson ET3 and PS Audio BHK for preamps).
All combinations worked well, but Pass Labs amp and BHK preamp is by far the best. No listening fatigue, great detail, wonderful full sound (with Pass phono preamp and MHDT Pagoda DAC). Big advantage of separates is the ability to keep mixing and matching.....
However, one change that really changed/tamed the 805D3's more than anything else was placing them on IsoAcoustic Gaia feet.
-GAR