I confirm the HEVC performance is surprisingly good. Did not encounter any issues. No lagging at all. Just superb.
The only thing that might not be great on the LibreELEC for Odroid C2 is the fact that USB Sound Cards are not supported.
This makes the few people still not using HDMI for audio not being able to use it properly.
Hope this gets fixed so I don't need to buy a Pi and stop enjoying HEVC.