Let the hive mind of Engadget get that for you.
"I am looking for a device that will stream sound from one source to several recipients. For example, I want to stream sound from my TV or stereo to my phone or MP3 player that has radio and Bluetooth capabilities. I have looked into radio transmitters and they seem like a decent choice, but I can't find one that uses external power (USB or from the plug) and I would want one with a transmit range of around 50 meters. Thanks!"
Wow - not sure where you got your $299 price from, but your own link shows:
"$149, $199 and $249 for the 5, 6 and 8 inch versions, respectively"
Still, frigging ugly. I'll stick to my AV123 "Rocket" 7.1 speakers in my theater, and my new AV123 "X-Series" 5.1 in my family room. Much better sound and value.