What AV amplifier for 4 x b&W + centre

Hmmm, just be aware that most dealers that have the MX-160 will likely have it all hooked to only McIntosh amplifiers.  I do know for a fact that the Mac amps are very laid back in the midrange (and overall).  It will NOT sound like your Classe 5300 and you could actually be dissappointed because of the lack of excitement from the Mac amps.  This may or may not be a result of the MX-160 processor, so if they can hook it to higher resolution amps, it will give you a better idea of what it will sound like in your system.

@mayoradamwest - why would you call MX-160 old tech?  It does use the new Lyngdorf DSP/processing hardware.  

The MX-150/151 is the "older tech" platform.

The 160 is nice and if just using for pass through it’s probably fine but lacks the latest HDMI HDCP 2.3 and most of the HDR formats like Dolby Vision. 

Well, I guess it depends on how current you want to be and how current your sources actually are.  The MX-170 does support those newer HDMI standards, but the retail is $15.5k.  That is, if you want to be in the "always get the cutting edge" technology mindset.

That’s why I think the 8805 is a tremendous value if your system is primarily a home theater.