I have this specific heater at work for 4.5 years, it does the job just fine, it produces a lot of heat, but it makes quite a bit of noise.

They say that you get what you pay for, and in the case of this fan heater, that might be true (purchased for 10€). If I had opinions on other models, I would be more certain. Its main disadvantages are the high noise level and the rather lukewarm, rather than warm, air it produces. Of course, these days we had freezing temperatures, but isn't that why you buy it? In the summer, it will be fine, it will emit heat! :p

Overall, it's not for much. Only for what its price implies. The noise, however, is a drawback. Don't expect to have it working next to you. It is suitable for situations where, for example, you watch a movie with headphones and don't want the light of a fireplace, which is why I personally bought it. It is not suitable for use inside the room while you work.