If u think about any optical drive the first choice is Sony. Lite-On and Pioneer are the followers. Your dealer is saying that the service of Lite-On is unavailable means he may be cheating, as Lite-on is better than what are he offering. Ask him to give a new Lite-On writer,else go to consumer forum. Before that visit Lite on website.If u want to elect any one from his options don't go for LG. Coz I and two of my friends are suffered many for LG optical drives. I have suffered for three times.

The best option is instead of taking one of these, ask ur dealer to give you a DVD-dfdl-Writer from Sony,which costs arround Rs4000.00. The CD-rw costs arround Rs 1400.00. You have to give the rest amount.