I checked out the features of Traffic 2004 (http://www.justflight.com) and found this at the bottom of the page:"ATC VoicepackThe package includes a custom voicepack. This voicepack provides additional pilot and ATC voices. FS 2004 per default only includes US American voices - the voices included in Traffic 2004 are US English, British English and English with German accent."I mostly fly GA planes so I'm not all that interested in the real airlines etc. I already have PAI for real airline names.The additional voices are very interesting however, because I do a lot of flying in Europe (Germany, UK, France and Switzerland). How good are the addition voices? How does FS assign voices to different airlines? Is it possible that you get a United pilot talking with a German accent etc.? :-lol

The voices aren't of great quality, but they are enjoyable enough. There are some names missing in the custom voice pack, usually approaches. You'll see the name of the aproach on your screen, but it won't be said. Also, the voices are assigned randomly. So in USA you can get a controller with a German accent.I'd say it's not really worth it to spend $30 just for the voices. If you also want the additional traffic, then it's worth your money.