What I have learned the hard way, time and time again is that third party, cheap batteries are never worth it. I am stubborn and I always hope that spending $10 instead of $40 is worth it. It never works out especially on Sony equipment.I usually get about 1/4 to 1/3 the life out of third party batteries than I do out of the manufacture's brand. I don't know why but I have had two Sony camcorders and the Sony batteries outlast the cheap knock off brand by several times.I have had two Canon digital still cameras and they seem to do a little better with the third party batteries than the Sony but if you want reliable, long lasting batteries, it is worth it to me to pay the price premium to buy the manufacturer's brand.Having said all that, this battery I bought is still functioning normally and has performed as advertised thus far.