To start with I would like to say that I have only used this model and not tried any other similar product with different make. So it is not good to say that this one is the best. I am using this model along with 135 Ah tubular battery for the past 3 years and till date it is working smoothly without any failures. There were times when we had to face long power cuts during day times as well as small power cuts during nights and this one was helpful during those disturbing period. It has got a ups and inverter mode which we can choose accrding to our requirements, obviously if we are using a computer, it should be in ups mode. They also claim that we will get sinusoidal ac which is similar to our line current and hence good for the devices.
Regarding the after sales service, they have toll free number which works in day time working hours and not for 24x7. free service against faults is for first year which seldom requires and after that it will be an expensive affair as they will charge a minimum amount for the service visit in between 400 and 500 and additional charges as applicable with respect to the work.
So to conclude I will recommend this product.