I bought 2 of these units because I moved and my window units didn't fit in the windows here. One unit has performed like a charm from day one. The other unit came on once and then the electric control panel died....I had to unplug it to shut it off. Customer service promptly issued a return label. The replacement unit was a tiny bit late arriving so I called...there had been confusion regarding when it would ship. That got straightened out and it got here quickly. The second one has been in use without trouble. I don't use the timer modes....just on/off. I would say they work well. I have not had trouble with the reservoir....though, while it has been hot here, the humidity has been low. The part that goes in the window is kind of flimsy but works, and was easy to install. Having said that, if I had my druthers, I would rather have a window unit. These crank out cold air enough to really cool the room that it is in but no more area. 2 of my window units used to cool the whole living area of my old house and that was more square footage and less insulated....and they had less BTUs besides. I like having access to and a view from the windows. However, my house is small and these portable units take up a bit of floor space. I haven't had an electric bill yet so I can't speak to the cost of running them. Under the circumstances, I am glad I got them. I have cool refuge areas in the house. I feel I got a very good bargain.....I would have paid considerably more locally. The company was quick to ship. Overstock customer service handled my problem quickly and courteously.