ok, the level6-license makes the difference, but the x64-box has advantages when it comes to flexibility and of course reliability in the field, nothing beats two power supplies
you can add fibre-cards if you want and do not need converters and overall it should be fairly faster when it comes to cpu-intensive tasks. or just think of oob-administration with the remote-access-cards made by many manufacturers and server companies. for a rb you need something external like a terminal server.
but both have their duties they are made for, so this is not the start of a flame, you simply cannot compare them.