As one would hope, this battery is lasting much longer on each charge than my phone's original battery, which has now been in constant use for two years. I would strongly recommend anyone ordering this product to double-check with the supplier whether they will be sending you a new, unused battery, and whether it has the "Sony Ericsson" holographic sticker guaranteeing genuineness. The battery I received lacked the sticker (it just had a small round, unbranded one that said "No problem"), and had the same impression marks as my original battery. In the case of my original battery, these impression marks came from the reinforcement mesh, inside the phone back, pressing down on the battery. Actually the new battery has deeper impressions than my original one which has been used for two years, which might imply use in a phone which has had rougher handling than mine. Having said all that, the battery's behaviour is what one would expect of a new battery, so I'm puzzled.