As I said - I'm having some issues here. Thinking about going into Apple tomorrow with these results. In Chicago, on VZ LTE they should be significantly higher.. no?
Try a real world test. Find a HQ YouTube video between 10-20 minutes long. Either check or reset your Cellular Usage at Settings->General->Usage->Cellular Usage. Reload the page and start the video. You'll see the video buffering while the controls are visible. Once the video completely buffers, look at the playtime or pause the video. Head back to your Cellular Usage and see what the difference is. Then, do the math. Video size divided by Time times 8. You multiply by 8 to give you Mbit which is kind of the standard.
Example: 20 minute video took 45 seconds to buffer. 100 MB used. 100 / 45 * 8 = 17.77 Mbit/s.
I was getting somewhere between 5-8 Mbit d/l on my Speedtest results and was somewhat disappointed, but after seeing the YouTube video buffer so quickly, I'm pretty happy.
Like most Apple stuff, you shouldn't rely too heavily on numbers.