I would rate SpiceJet as best among all low cost carreirs( LCCs) flying in indian air-space. Simple reason being that one can find all sort of fares to one’s suitability. Though, they have quite few destinations covered, connectivity amongst them is very good. One can expect to get dirt cheap tickets if ready to fly at odd hours and even cheaper if you take stop overs.
I have flown with them 4-5 times on delhi-pune and delhi-goa sectors and its worth the money. Only airlines which can be compared to it, is Air-sahara at the moment where you can have food served on almost same fare prices. Besides, cancellation charges are not that much as compared to other low cost carreirs( LCCs).
Webiste design is awesome, I must say. Given a chance, I would fly with spice-jet or air-sahara. Would write about air-sahara in their category:-)