Hay dani_cain,
Try updating your profile & prl in settings- system updates.
I'm running 2 epic's one stock and one rooted, only updated stock and i seem to have improved connections with 2G &3G. I ussed network monitor from the market and noticed better speeds on the stock updated epic touch. I'm the city so we have great connection speeds here in NYC. Updated phone has had no issues whatsoever since update, will keep rooted phone as is , maybe update the modem, i get 16580kbps on downloads - 383kbps up on wi-fi, 5217kbps down - 1426 kbps up on 4G, 1230 down - 781 up on 3G this is using speedtest app from market. Download and check your speeds.