I too have an 04 550, but, mine doesn't sound like the one in the video, at least not as loud.
However, it does sound different than any other bike around. It has a lot to do with the straight cut gears on the primary nut, and clutch gear. They are noisier, but, stronger than gears cut with an angle. They make a whining noise when revved. Like I said, my bike doesn't sound like the one in the video, at least the whining noise is not that acute, but it is there. I wonder how much the recording device itself has to do with this sound, ie, is the microphone or audio recording card more sensitive to this particular frequency.
As Steve pointed out, there is a chirping noise that comes from the intake that becomes more noticeable in the midrange, kind of sounds like an old VW beetle exhaust. All the bikes with FCR's I'm pretty sure have this noise to some degree or another, but, because of the air filter arraingment on the berg you hear it much more.
The main thing you need to know about buying this bike is how many hours and miles are on it, and it's maintenance history.
