I bought the B&W DM603 fronts, CC6S2 center, and DS6 surround speakers about 8 years ago.
I used them with Adcom amps and processors, but recently upgraded to Outlaw 990/7125/LFM1+ combo.
The B&W speakers sound even better with the Outlaw products.
Even thought my B&Ws 8 years ago, I've had no need to upgrade.
I know B&W also makes high quality in-wall speakers that you would be loking for.
For the sub, I'd say get the Outlaw LFM1+. I love it.