Opinions about Sony Ericsson C510

Hello. Guys I am planning to buy a Sony Ericsson C510 from a friend. I needed your input on the device about its performance and battery. Specially battery life is very important for me and the cell phone should run around 3 days with normal use. Any ideas?

There are phones with better specs and whose price are slightly more than the aforementioned:

Sony Ericsson C901 Rs.14800

Samsung S5550 Shark 2 Rs.14500

Samsung S5560 Marvel Rs. 15,600

Thanks for your suggestions. But i want some input on sony ericsson c510.

my vote for Samsung S5560 Marvel.