In my HT I have an 861v6 and a bunch of Revivers, used to have 5.1 now thanks to a HH'er in UK and Chris in the ex-Meridian shop I now have 7.1. I refused to invest in this until I figured out a method to get HD 7.1 audio through my media player into the speakers. Once I figured that out, I bought the last speaker and I am very happy.

But you should inventory your Blu-Ray library to see how many 7.1 soundtracks you own. Out of my 379 BD's and DVD's, I have only 23 7.1 soundtracks, while I own 139 2.35/2.40 widescreen films! So, Cinemascope I invested in first, with a JVC 1080p projector and a lense+video processor and a 2.35 screen.

Some directors take special care with their 7.1 soundtracks, such as LoTR's Peter Jackson, David Fincher's films, plus Oblivion.

TLDR: Glad I finished the upgrade to 7.1, very happy to have invested in 2.35 screen/projector!

Primary: 818v3+ID41, M6 stereo pair, M SpeakerLink cabling, Sonos+96kHz Cullen, silver DSW
HT: Marantz prepro, 271, DSP3300, 8K SE FL/FR pair, DSP M6x2, DSP320x4 (ceiling), black DSW, 520 RL/RR rear in-walls
Living Room: G65, 640 L/R in-walls, UHD722, MS600
Vac. Home: G61, HD621, 4xDSP3100, DSP3100HC
MDMS:NUC/ROCK+TrueNAS Core 12.0 ZFS file server