Test preformed in Mission, Texas.
Obviously, 3G won't get the full benefit of HSPA+; but the backhaul upgrade should allow 3G to max out more frequently as 4G users spend less time choking up the channel. At least in theory.
Upload speed has varied greatly, between 300 kbps to 2000 kbps. Download speed has gone up to 6000 kbps, averaging around 4000 kbps.