He's concerned with 1080p playback I bet 5.1 would be fine. Atmos on a unlicensed 40 usd device? The cheapest atmos soundbar costs $1000. By the time most people jump on atmos surround c2 will be long replaced.
The thing people wanted more from odroid c2 than atmos and it hurt their sales for almost a year was proper iso bluray playback and ac3/ lpcm 5.1 surround support for their older avr's. There are alot more people who don't readily upgrade avr's because they are too pricey to do that. The amlogic sdk just didn't supported it. Sadly only just recently did odroid get that fixed.I think thats the biggest issue with ordoid vs rpi. The specs may be better but the support is just not in the same league.
I wouldn't waste the xtra money on the odroid c2 when a s905x with vp9 and hdr could be bought cheaper. I don't see it worth the extra money to bother with the c2.Its life span will probably be the same. I paid 44 bucks cad last summer for one and 5 bucks for an sd card that has 2.5 megs a sec writes on the small 4k.