I bought Microtek UPS 850EB inverter and Exide 1500 inverter plus battery for 2BKH flat two year back due to increase number of load shedding during summer season. I bought it for approx 12K with all installation, battery and inverter. Its a In last two years only thing, I have done is check & maintain the battery water level.
During installation, the installer had connected directly into MCB which was wrong. It should be connected to a box for safety of the instrument.
Many a time, I run my washing machine (dry only) when the lights goes off during washing. It works fine.
Once, the electrician had added excess battery water. due to which I could see white powder like substance deposited on body. But simply cleaning it with dry clean clothes removed it. Now we are careful while watering the battery.
One I notice is buzzing sound which it produce when light goes off and their is load is on inverter. But the sound is minimal and not irritating when fan is on. When we go out station for longer duration, we make sure to switch off inverter along with MCB.
Overall, I am satisfied with the Microtek + Exide combination. I feel that the battery like Exide has better performance compare to other one. one should be careful in specially selecting battery. Only issue, I feel is service which you have to carry the heavy batter to Exide service centre.
Note : This is not a legal/professional advise, it just a personal opinon. Use information at your own risk.