I will not say its a bad water heater at all. Actually I used it for quite sometime but the thing is not its functionality but its reliability. I used it for over a year but I didn't satisfied from this. The water heated will not come out due to some gas stuck inside and come out very slow. Not useful when you are thinking to get ready in the go.
Take like 10 minutes to fill a bucket. Then there was the problem of heating indicator that shows water is completely warm and turns off itself once I turned it on and it got malfunctioned. Thinking the water is heated I turned off and took a shower but the water was ice cold.
After that I had no idea when it got warm and when to turn it off. Its a little thing but a lot of trouble. Then I had to remember it to turn off after 40 minutes which was kind of frustrating. I really won't say it bad but its not something you get when you use a simple thing like a water purifier.