If anyone is interested in some reference: running 15mph is running the same speed as a 4 minute mile (or 60 seconds for one 400m lap). That's not to say that Kmac can run a 56 second 400 (that's what his mph conversion would come out to) but he has the speed to run at least a 14-15 second 100. For a guy his size that's pretty great.
Running at 20 mph is equivalent to running an 11.25 100m dash (if you were to sustain that mph speed over 100m). Tyler Byrd running 23.7 mph is amazing. In the World Championship final in 2009 where Usain Bolt set the world record of 9.58, he averaged 23.3 mph. Now, during that 100 meters he reached speeds of 28 mph, but his average was 23.3. Byrd can't break 10 seconds for a 100m, but he can reach a speed that would enable him to do that, so for route running and shaking coverage he should be lethal.
Fun fact, Kongbo runs about as fast as a polar bear.
