Its most widely used in India as Internet Service Provider(ISP).there are some point use must see or consider before planning to use it.
positive points:
-good service plans
-internet speed is good
-internet service plans are reliable
-gives more offer and free internet as offer
-lower cost
Negative points:
-not satisfied with customer support(sometimes) 3/5
-frequent internet issues(once in 2 month or more)3.5/5
But if you are looking for low budget and higher unlimited plans the just go for it.