P.S. For music listening even the DAART Canary II is definitely better than G6. Given the HD800 resolution and amp scalability both G5 and G6 would under-perform. For films and gaming I would recommend keeping G5 and probably feeding from it another DAC/AMP through Toslink, as I am doing now...

I have both. When testing with (a modest) AKG K612 Pro and Dune 2021 soundtrack (48/24) G6 gives more clear and defined bass notes. G5 sounds comparatively more muddy with busy tracks. I hope to compare them soon with DAART Canary II and report.