I recently purchased the extended battery from VZW for $37 after discount. When I purchased this battery online, I was extremely dis-satisfied with the battery life of the stock battery. However today was a completely different story. Battery life was acceptable , almost great, lasting over 13 hours. My question is, if you guys think that today was just a fluke, or has the battery adapted like HTC said it would? Should I return the extended battery or keep it? Thanks in advance.