I have a Honeywell heater I run 24/7 in the winter weather. This thing runs non stop day and night for several months straight.
I also have the furnace set to cycle on and off when the electric heater won't keep up.
Although I am conscious of possible issues running a heater all the time, I don't have much of a choice. Fulltiming in a 3 season TT requires a lot of heat to keep it livable. Not too bad right now when the temperature is only a couple degrees below freezing but tougher when it gets minus 30C and more.
I do check my wiring periodically to make sure that things are not getting hot.
And one key thing that gets overlooked with a lot of folks is the 30 to 15A adapter used. I am plugged into a single 15A plug so have to use the adapter. The el-cheapos can actually melt and cause a problem. I know, I have one here that did that. I smelled it cooking last winter so changed it for a really good one.
It would cost me a lot more money for propane without the electric heater.