I have been flying Jet since the past 6 years and found that they are one of the most punctual airlines. However, their food quality, taste is really BAD on most sectors. Packaged beverages, water and desserts often smell of plastic and food is sometimes very hot and absolutely non platable. While the ground staff is courteous and seems to be alert to all your needs, I have found that off lately, the on board staff is faltering a bit on their mannerisms.
The airline gets a Good rating only because few other airlines in India match up to their punctuality and courteousness. However, seating space in the economy class is a nightmare when it comes to more than 2 hour flights. No elbow room and if you are slightly overweight, you tend to stick into your seat. In many sectors, cabin comfort is compromised by reducing air pressure (Indian is the best in this regard)