swapnil, i hope by now you would have already upgraded the bulbs.
I went through similar situation. I was looking for simple bulb replacement for my Verna. My stock bulb spec was H4 60/55W. Was confused between Osram NB+ & Philips extreme vision. After going through several online reviews, the info i received was Philips has better life than Osram.
So decided to go with Philips extreme vision H4 60/55W. Philips website suggested AK Traders in J C Road, Bangalore as the one of the authorized dealer. So bought 2 bulbs from them. The price was Rs450 for each bulb. Fixed the bulbs for Rs:50 from a local shop. Now I know how to replace the headlight bulb.
I can feel a definite improvement from the stock bulb.