OK I switched to Lenovo's stack at last cause the built-in stack doesn't send files to my Android devices reliably...
- More built-in drivers included, including one for Bluetooth headset which I had to download from somewhere before.
- The Bluetooth icon becomes more ugly.
- As more drivers and Bluetooth profiles are supported, it brings up an extra icon for the Android device under Windows Explorer as well.
- It adds a "Bluetooth Devices" folder in the Program Menu.
Edit: Scratched that, the Lenovo stack doesn't send files to the Android device reliably either.
Even worse, the headset becomes unusable in Skype.
Uninstalled and move back to Windows' default.