The battery is well packed, it may happen you nothing and the change in my RS800 is no problem at all sure. If I set the clock every 2 days use with chest strap and bicycle or foot pod, so I come to a change every 4-5 months. Do I still have to run the GPS, then it seemed to me as if the life at max. 4 months, but may well be related to that was trained more in the period of use of GPS.
Because the price is anything but blows up the life perfectly fine and I can only recommend the battery. Had 4 pieces bought and all 4 have their purpose fully met. Now I have ordered again.