Fan noise-what's irritating to one might be acceptable by another. Has to do with frequencies and how we interpret them. I have had a variety of small electric heaters. The most efficient is the chinese built tin case and 1400W of usable heat. Unfortunately, they are built with quality as an after-thought so durability is really bad. Currently, I have four that are now carcasses for the scrapper.
My current fave is a Honeywell oscillating "energy smart" heater.It can be thermostatically controlled and puts out a very quiet air stream. We also have a Westpointe 1500w rated heater that is the smallest and has three settings-fan, low fan and heat, fan and high heat. It is the noisiest one we own but outputs a fair amount of heat.
I like the "try and exchange" idea and that may work for folks that shop at a big store, a lot, or are close to such a store.