I have one. Absolute junk. I don’t know why I didn’t throw it away last year when it failed to keep my small motorhome at 55 degrees last winter, but now I’m taking the garbage back to WalMart for a refund.
these small heaters are all 1500 watts
that’s basically what you can get out of a standard 110v outlet
fancy case, oil filled tubes, “ceramic”, fake fireplace, yadda yadda
they’re all basically 1500 watts
obviously there’s some differences in robustness of construction but the heat output is all the same