My Mugen 2400 mAh battery gave just the extra juice needed to get through whole day with heavy GPS-usage and surfing on remote cities. With an original N900 battery I always have to charge middle of a day or have an extra battery with me, but re-booting in middle of a day is no fun. With the reboot, about two original batteries gave the same usage time as one Mugen 2400 mAh battery.