You also appear to have the fastest 3G in America.
3G ping times are usually awful. 4G ping times should be better.
Ping and latency are how fast your computer gets a request out and back. Gaming is pretty much lots of quick information bursts being sent. Each side has to send and confirm and exchange data. When you are just downloading, one side just sends and the other side listens. It would still be 'slow' to get started initiating the file download, but once started, you're flying since one side is basically just listening.