All the sine waves have been taken during running a PAK pedestal fan 150W. Almost all (excluding last 2) UPS are "Modified Square Wave" type. When no load, wave form is ok and when load is connected, wave form is distorted.
So it has been proved that the best available UPS in affordable price in local market is Systek. After these tests, i bought Systek ECS-202 and replaced with my old daisi UPS.
For running 4fans and one light, old daisi UPS was drawn 40A from a 12V battery
After replacement and with same load, Systek draws 15.5A @ 24V (and thus 31A at 12V). So the back up time increased by almost 1hour. I found excellent features in Systek, a good charging system and under-over volatge protection of battery. Internal filters made the output wave form smooth even in fan load for which the wave forms of other UPSs are distorted.
The efficiency of above UPSs will be informed latter as the work has not been completed yet. But according to initial tests, Systek is also better in efficiency because of a "near to sine wave" even in inductive load condition.