I tend to stay away from OEM products but thats just my opinion. Ran into too many issues with them. But I do run the Audigy 2 Platinum with the Audigy 2 Live Drive Bay.
Unless you use 1394 devices or plan on doing any sound/video work then there's no reason to spend the extra money. By sound work I mean inputting guitars, keyboards, camcorders, ect... But it is pretty nice if you have a DV camcorder and such. I typically use mine for my guitar, camcorder, and the accessibility of the front mic and audio output ports.
Also there is a remote for those of you who use your system to play MP3's, movies or just plane ole cd's. I have no clue where my remote is though..lol.