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!"
It could very well be that AT&T has a very crappy network. I use to work for them. They have very crappy service and unreliable networks. Try bringing your 5300 to Canada. Rogers Wireless has an AMAZING 3G and 3.5G network and is Very reliable. The only time I've lost 3G is when I’ve gone way out into the middle of nowhere lol.