[wrxtasy]

- I use TVHeadend (with a SAT>IP server) on my NAS and I have found switching times in MrMC to be slower than in Kodi 17 (LibreELEC 8.2.2.3) or Kodi 18 Alpha (LibreELEC 8.90.2)

I'm not finding channel switching times any different between MrMC (Kodi Jarvis) vs Kodi Krypton with TvH and predictive tuning turned on. Most SD channel switching are almost instantaneous.

This may be due to older version of Kodi that MrMC is based on, so a lot of PVR optimisations are missing.

I would not say a lot, but the one thing I do miss with Kodi Jarvis vs Kodi Krypton is the Smart Recording features.

The deinterlacing (Yadif 2x) on the Apple TV 4K looks nice, but on 1080i channels, I have a lot of dropped frames.

I do Not have dropped frames with 1080i H264 streams.
There is a bug in auto deinterlacing with MrMC , you have to go into video settings and hard select "Deinterlace" for YADIF 2X, then set as default down the bottom.

For 480/576i mpeg2 TV streams (25fps) you can also turn on Video Post Processing to clean up the picture output a wee bit because the ATV4K has the CPU ponies to handle that. You cannot do that with the U9.

For 4K, well both devices would be fine. I'm not seeing major differences apart from the ATV4K's slightly superior 1080p > 4K picture upscaled video output when using non Kodi Apps. Remember LibreELEC Kodi Krypton on the U9 can do Auto resolution switching, the ATV 4K cannot, but in reality it really does not need it anyway.

I would not use the TvhClient App on the ATV 4K, last time I tried it was buggy and support was lacking.

MrMC has built in Plex, Emby, mySQL and TrakTV clients that are configurable from the Kodi GUI:
https://wiki.mrmc.tv/index.php?title=Main_Page

The ATV 4K is the superior Apps platform, especially for International (that needs 25fps / 50Hz support) and local Apps integration, plus superior auto frame rate and colorspace matching (for SDR / HDR) that operates on a system wide basis, not just Kodi or Plex.
Anything Android does not even come close and actually feels like a US-centric WIP Operating System by comparison.

LibreELEC Kodi Krypton is definitely superior on the U9 if you want the full monty Kodi experience.