The data transfer usually works well, but a few specific Samsung features and their data may be lost or have to be transferred manually. It is recommended to make a backup of important data before the transfer to be on the safe side.
Yes, the Nothing Phone (3) comes with a protective cover in the box. According to the official Nothing support page, Nothing Phone (3), user manual, safety information, screen protector, SIM tray ejector and protective cover are included.
The Nothing Phone (3) does not currently support Bluetooth LE Audio. According to available information, Nothing has not yet implemented support for Bluetooth LE Audio and the new LC3 codec, although this technology would be possible with Android 15 and Bluetooth 5.3. Other manufacturers such as Samsung, Google and OnePlus already offer this function, while Nothing still has some catching up to do.