A few people tried them out over in HOCP's display thread and said they're decent. They're also a bit cheaper if you get them online, $50 at HSN I think. Probably similar to a pair of $50-80 PC speakers. They do add the nice functionality of a remote and no desktop footprint being integrated into the 2485W itself.
Depending on what you're planning to use your 2485W for, you might want to look at a dedicated A/V set-up. The Gateway TDX sound bar is tied to your PC, so you won't be able to playback audio from external sources unless you run everything through your soundcard. Most cards nowadays are cutting back on the number of inputs on the back of the card, but something like Creative's face plate would allow you to do this. Still, everything will be in 2.0 stereo and most HD sources nowadays are capable of 5.1-8.1 DD/DTS/THX.