i will be going by this train to chennai next month.if anybody who has gone by this train before kindly tell if there is need to get ticket now as i see lots of seats available for all days.and what about the security as many seats in sleeper class are vacant from delhi to chennai and about the food also and does it reach chennai on time or not next day..i will be going in sleeper class and i see lots of seats are vacant each time train goes to chennai....thanks in advance...