I have been using Usha fibre body 15L storage heater for the last 3 years in one bathroom and Inalsa metal body 25L storage heater in the other bathroom for the last 1.5 years.
The best thing that I liked in Usha was the temperature setting functionality. Also, the heating is quick and the heat stays for a long time.
The thing which I didn’t like about Usha is that I had to change the body tank twice. Luckily, I have 5 years warranty from Usha for the tank and hence, it hasn’t pinched me yet. But, I think that the body isn’t very good if it starts leaking every year.
In comparison, I got 25L Inalsa for almost the same price as that of Usha with the same 5 year warranty. I am extremely happy wih Inalsa. It has a dual coil and the heating is really quick(quicker than Usha) and there has been no problem yet.