Sony Ericsson W300 / Z530

Im having issues with both my wife's W300i as well as my own. Battery life sucks big time! I charged it last night and talked for about 45 minutes since then. This morning it has 65% battery left. No bluetooth, no games, no photos, no memory card and all the power saving features are on. I called At&T and the man told me to get radio Shack to give me a new battery, and use it until it died then charge it back up for 2.5 hours. I did this but the manager at Radio Shack gave me the battery from the display model (over my protest) he told me it had just been put up. So what do you guys think? Am I crazy here or do you think this is normal? Our 2 year old LG C2000 last longer than these things.
Thanks,
Will