Speaker suggestions to partner Cyrus 6xpd and sonos system £400 budget

I have bought a used Cyrus 6xpd amplifier at a bargain price and will be using with a sonos set up.  I was thinking about getting B&W 685s as I liked my B&W DM602s I have had in the past.  Any comments on the match for this set up or any to put on my shortlist? Max budget £400 have to consider used speakers too!