It has been 20 years since I used one of these set ups. Back then it was, "Which one works with plasma televisions?" Are there any issues with newer televisions and functionality?

I’ve been using CEC very successfully for the last 4+ years.  Current AppleTV and Xfinity remotes allow for automatic switching and power control of all the gear we are currently using.  Clients are very happy with the setups, and the money saved on control can go toward things like better speakers that the client can get more enjoyment out of.  YMMV, but I’m doing fewer truck rolls and referrals continue to be strong.  I’m also much happier not having to deal with control system headaches.

New gear, yes, what to do with a 8-10 year old receiver that’s in the system? I default to IR in that case.

If you want 4k, HDR, Dolby Vision, 120HZ, etc. etc. to function, you need a newer AVR.  That said, I've still had pretty good luck even with older receivers and CEC.

Is there general use or best practice for how to actually control individual components with CEC? For example I discovered by accident to hold down home to turn off the Apple TV. I recently did a Sony TV with a Pioneer receiver. Turn on the TV and the receiver turned on to the correct input. But turn off the TV and the receiver stayed on. So now we need the pioneer remote.

I stayed away from CEC for a long time but due to the cost of basic control systems I’ve been using it more. I just find it’s not as clean. Toss in a second source and it gets worse.

Craig

I had a recent issue where a Blu-ray player was shared by multiple TV's. When I issued a power command to a Samsung TV in one room, a Sony TV in another room would start. I had to install a CEC blocker in the Sony's connection to Blu-ray.