I just got my mx700 tonite and it's awesome .. really good response ...
Answers to full charge and usage questions
Q: How long should the mouse take to reach a full charge?
A: After a complete discharge, the mouse will take four to six and a half hours to reach a full charge. Charging the mouse for 15 minutes gives the mouse enough power to operate for one day of standard use. We recommend you fully charge the mouse as often as possible.
Q: How long should a full charge last?
A: On average, a full charge should last about ten days for a standard office user. Some "heavy" users might need to recharge the mouse more often. Low cycle times (one to three days before the unit has to be recharged) may indicate that the mouse never powers down as it is designed to do during inactivity periods.
If u have more questions .. go to the logitech link provided here
LINK
CheungMoKee