If you are using a 271 you can use the 818v3 connected to 271's SpeakerLink input and suffer no 2 channel limitations while using nearly any other surround processor. I do this at my place and get full MQA and the best surround experience using a Trinnov Altitude 32 8 16.

The Lyngdorf would be the next best followed closely by the Storm in my opinion. All have been extensively tested in my speaker setup. If you use a 861v8, a network failover switch can be used to switch the SpeakerLink connection of the 861 and 818v3 if using a daisy chain configuration. If using home run, two network failover switches would be used. Not a elegant solution but it works well in situations where you have multiple SpeakerLink output devices. With a 861v6 or v8 you can use the 818 in the SpeakerLink chain but that's when things get complicated in setup.

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One step from the Presidency
#1 Trinnov Altitude 32-8-16, 271, 8000XE, 7200SEHC, 7200.2, Seaton F18, JL Fathom F113, Revel w990's, Kef R7, ATI 528 Amp, JVC RS4100K, SI screen. Roon Nucleus+, Eno AG, Eno M link, 218.
#2 Mark Levinson No5105, Ayre VX8 and CX8, Vandersteen Treo CT, Preamp varies.
#3 Meridian Ellipse