There are low tech and mature products. As I found, almost verything made in china. The brand name makes no different. I prefer a oil filled heater. It heats little slow, but silent ,even and does not dry air.
most heater at 700w to 1500w. You can't go higer. Since we use 110v and 15amp plug. the max safe W is 110 X 15 = 1650W.