I don't use electric heaters in my camper, but having sub-basement bedroom have been using them for years there.
For the house oil-filled heater is the best, but it is big and heavy for RV.
Ceramic heaters are very small, but the fans on them can be annoying and they are the first thing to fail.
You don't want anything in RV, that is showing red-hot elements.
I like baseboard heater if you use it often, but that still might require additional heater not only for better heating power, but also for air movement.
One thing to remember, 1500W means 12.5 amp and you better make sure you have good connection for it. Use contractor-grade extension only and if you have aging power outlets, you might want to upgrade them to 20 amp and hospital-grade.
Our neighbors lost their house couple years ago when wall outlet overheated and ignited wood paneling.