Microsoft’s supplied Bluetooth transceiver sucks. So, if you don’t already have Bluetooth abilities, then Microsoft’s solution will be cumbersome and you’ll probably want to buy another Bluetooth adapter. So, in this respect, the transceiver is definitely two thumbs down.
However, the mouse is good and works well with other Bluetooth transceivers (namely the Sony Bluetooth Adapter) and gets thumbs up. The mouse shouldn’t be penalized for the transceiver it comes with.