From Yamaha ? Reliance digital have their own service team and provide additional warranty which is not brand warranty. I have also used Yht299 for 3 years which i purchased from reliance digital. Their service team is good with tv,fridge, washing machine etc not sure how knowledgeable they are when it comes to HT
I don't think it is worth it. If nothing has happened in one year, it is unlikely that something is going to happen in the next couple of years. Moreover, repair is quite cheap in India if you live in big cities.