IRCTC is no doubt a great convenience to all, specially avoiding queues, booking ticket at right 8 AM or tatkal etc. Though it simply hangs at exact 8 AM when booking opens, still the site is now much better than what is used to be previously.
My had a difficult problem with e-tickets TDR process. I booked one ticket PNR number 4408238912, and had forgot to cancel before departure of train. Normal process is to submit the ticket and get a Ticket Deposit Receipt ( TDR) and apply for refund. Though IRCTC has provision to do that online, I still have not got refund after 6 months, where normally 3 months required.
So, beware - if you buy e-ticket, be sure to cancel on time, else IRCTC will not take care of TDR refund !