He may be a one trick pony, but it is one hell of a trick.
The X factor for me in this fight is out of the cage stuff. Hendo is a low key guy, while JBJ has had to spend time dealing with "other" stuff. But based on the pictures it appears he is using the gym to escape that stuff which could make him more of a monster.
Either way, JBJ should win this as long as he keeps Hendo at range and make him pay for coming inside.