RoGuE_STreaK , I have a nano clone with a 2oomAh battery and it returns between 5 and 6 hours playtime but this can very depending on what settings you are using. LCD type, EQ settings, volume setting, earphones and how well the firmware is programmed will all effect the battery life. The manuals are generally generic and sent out with many different players as are the mini cd's so it is not unusual for them to contain info that is not relevant to your player.
buy.mall! as you say is one of the bigger scammers so he will be fluent in giving you the run around.
I would suggest be persistant and not give in to his initial offers which will no doubt be measely. If you go via PayPal and eBay be sure to inundate them with pages of information on hacked players, your personal findings and other feed back from his buyers. Just as a test I would also suggest that you visit the petition I set up and copy all the comments left buy those that have signed the petition regarding buy.mall! and even link them to the petition. It will be interesting to see how they respond to this
http://www.petitiononline.com/eBay666/petition.html