Let the hive mind of Engadget get that for you.
"I own an iPhone 3G and I'm looking for a decent speaker / alarm clock for it. I am going to listen music in a mid-sized room, so I want nice quality speakers with solid bass. I also want to use it as an alarm clock, so it would be great if there is such a feature. The price can be low-mid to mid-high range. I was looking at the Klipsch iGroove SXT; it's powerful, slick and the reviews are good, but it doesn't have an alarm clock feature. It's no deal breaker if I can set it up from the iPhone, but I'm not sure. Thanks!"
A friend of mine just recently bought the xtreamer, and its really quite a nice little unit, I've purchased an older emachines sff machine with an onboard geforce 8200 and hdmi out which is a perfect candidate for xbmc as the gpu fully supports vdpau, and has hdmi out.
Along with the comparison, we need to see some video of these working, it could have all the features in the world but have an ugly slow interface no-one would ever want to use.
show us!