My testing is in! or done. Something like that.
Yes, Nostromo is right. Mostly downtown. I got the best signal around Elitch Gardens, and the Pepsi Center. Some signal over by Mile High, but nothing actually in Downtown Denver.When the phone did switch to 4G it was either no, umm, curves?, above the 4G icon. Or just one of three. I did get 2 of three once. Which gave me (according to Speedtest.net's app) 2721 down and 1031 up. With no or 1 curve, 3g was faster.
Keep in mind, these are still in the testing stage. They are not full blown running 4G towers and networks. I had to test on the move. There were several games and other events going on, plus construction. I only got to stop the car at traffic lights. It is nice to see my phone go into 4g mode though!