Amplifiers for B&W 803D/802D

I'd go for the 803D. To me they're better balanced and can work off the lesser power amp but they still need plenty of power. I would recommend 803D with either MC501, bigger Classe, Pass X250.5 or X350.5 or the bigger Levinson amps.
I heard 803D and 802D and I honestly think 803Ds are a better choice, unless the room is gigantic.
Don't forget, 803D are capable of playing very loud very clean. All they need for that is a proper amplification.
Regardless of which of the 2 speakers you choose, I don't think MC402 is the proper amp if you want uncompressed dynamics and soundstage. MC402 would be fine for low level listening for 803D but it would not do the dynamics the way some of the other amps would.
With B&Ws, amplifier is the most important component.

Statusnine, McIntosh and Pass are very different amps.
X250.5 is a 2-ch amp, 250w/ch into 8ohms. It doubles into 4 ohms. It's a different design from MC402.
X250.5 provides about 36 watts/ch of pure class A which is great for low level listening. Also, the Pass amp is more dynamic, effortless and explosive than the McIntosh. MC402 is a fixed 400w/ch no matter the load. B&Ws will dip into a 3ohm territory where the X250.5 will have an advantage over MC402. I heard MC402 with 803D and own X250.5 and to me the X250.5 is a better performer.

Bottom line is - you got to do your own research which should not be limited to these forums. Listen to as many amps as possible and draw your conclusions from there.