I think Frank is well-spoken and I like him as a fighter but I really think he's biting off more than he can chew. Granted, you'd have to be crazy to turn down a shot at the HW strap, but I think JDS is way more than he can handle. Mir doesn't have the extraordinairy chin needed to eat shots from JDS, and I think JDS is going to be able to keep him at range and nail him with shots until he shuts the lights off. While Frank's BJJ is sick, he's never had overly impressive takedowns and JDS is a big, athletic guy who is really going to fight each and every takedown.
I see JDS winning this early by KO.