For real sound quality difference, get the x4800h or C40, after adding $800 for DLBC, it still costs you less than $4,000. Actually less because DLBC is for them won't be available until later this year or even next year. Brand new with the latest feature, though the MX160 isn't that old, but for $4K, that's old, and used? I wouldn't do it, old power amps are fine especially McIntosh's but not a 4K 11 multichannel avp.
Or for $3399, the Anthem AVM70 is also a better value, brand new with HDMI2.1, HDCP 2.3. Anthem's ARCG is not as good, but if you how to tweak with the app, it can do a good job too.