I have traveled by this airline several times. And I would say this is one of the worst Airline services in the world.
One and only good thing about this airlines is that the fare is lower than few other airlines.
Spicejet has got many Issues.
When there is a plan for change in travel date you will have to pay more in this Airlines when compared to other.
During travel you will not be offered anything like Tea/Coffee or food complimentary but if you need you have to buy it by paying too much. It will be very expensive.
Most of the planes are small so you can not expect a comfortable seat. It will be very congested.
Often Spicejet Airlines get delayed in service.
This is my personal experience so I do not recommend this.