I have owned 2 3500 batteries I bought on Ebay about 8 months ago. With one of them I tried a few different things (like wiping battery stats) to improve the length of charge and the other one I did not do anything to.
8 months later, the one that I didn't mess with holds just a good a charge as day 1. The other battery that I devoted a couple of hours to, just to make it last longer, now only lasts about 24 hours.
What I am saying is that I don't think that there is anything that you should or shouldn't do, just put it in the phone and use it like you normally would. There is no way of telling how long a battery will last and there is not much you can do when it decides that its useful lifespan has been used up. (unless you have dud and/or you have a warranty)
