Hi KJ,
Only a block heater. And the storage yard doesn't have power. I do have solar, and a battery bank that could power the block heater--but training the staff at the storage yard is pretty much impossible. I do have a Trik-L-Start, so the chassis battery is always pretty much full.
I use 5-20 synthetic oil (Amsoil).
I have had no issues with plastic breaking--but then I've always "warmed up" at home first. Now that I'm full timing, that is no longer possible. See my thread on heating electrically.
I don't use a television. I do keep computers in the RV--but they don't get turned on until they have been warmed to room temperatures. If I get a TV I'll do the same with it.
I do have a heater in the compartment where I store my cords, but I need to bump up the wattage.