I travelled from Chennai to Delhi on 23rd December 2006 and my experience was good. Due to bad weather in Delhi quiet a few low cost airlines were getting cancelled whereas these guys assured us that they will not cancel our flight and kept their word. It took off from chennai after a good 4.5 hrs delay but it did go to Delhi. I had to catch a train in the night from Delhi.
Inflight experience:
Their flights are brand new, clean and the seats are pretty comfortable. Much larger than Jet Airways flight seats. The air-hostesses were really beautiful and their hospitality was also good.
Snacks:
They have the normal tropicana, coke cans, peanuts and cookies. Sold at MRP. Mineral water is obviously free and you can have as much as you want.
Pilots:
I did have look at the pilots. They are no young people. The captain and the co-pilot were senior people around mid-40s atleast in the flight I took. The landing and take-off was pretty smooth like anyother airline.
In general I would say, these guys are low cost airlines but good that they dont compromise on quality.