I managed to get CNET's bandwidth speed test to work. I was able to get 403.8 Kbps from my current location. I'll run some more tests in different locations to see if I can figure out how reception affects the speeds.
I looked for configuration options for EDGE. Don't appear to be any. Not sure why you'd want to change them, but anyhoo.
CNET speed test: http://reviews.cnet.com/7004-7254_7-0.html