I considered flying from New York back to London with Air India back in August because their prices were so low ($370 compared to $700-$800 with the other airlines), but then I found some not very complimentary online reviews about the flights and decided to play it safe with a more expensive flight.
One person complained that it took her 3 days to get from Chicago to India with them - they kept cancelling the flights out of Chicago, so she had to spend 2 nights in hotels there. Someone else said that they found the onboard service terrible and that the plane interior looked like it was falling apart!
I'm sure that not all their flights have problems, but I decided against booking a ticket with Air India just in case and in the end paid $800 to fly with United instead (the next cheapest airline I could find).