I was looking for a Bluetooth mouse with a good grip for a portable work in Windows 7. This Logitech M557 meets my wishes: - Comfortable to hold as with other Logitech mouse models I use. - Power on / off (essential for my use). - A button to pair (easy and practical) which market the first blow with the laptop Windows7 Windows8 a tablet and an Android tablet. - Sensitivity and sufficient reactivity for a mainly office use. I can not comment on battery life (mice received today). Price a little high for my taste, but acceptable under characteristics.
