Florida runs a lot of different formations. Here are the problems they pose:
If Monte runs a nickel as the base defense that day, UF will come out with 2 RB's and Hernandez lined up wide, and then just move him into the backfield as a HB to give the Gators an extra blocker. They tear people up in the run game in that scenario.
If Monte Stays 4-3 then UF will just line up with 2 RB's but then motion Demps or James to the outside and suddenly the 4-3 is matched up against 4 wide.
The best defense is probably a 3-3-5. UF uses a 335 package and they call it Joker. They use it against spread teams and bring 8 guys to the LOS with maybe only 2 guys putting their hands on the ground. So the opposition never knows where the rush is coming from.
One play it might be 3 linemen, a lB and a CB, then the next, it could be both safties.
THe big key though: You really have to mix it up and you have to play good assignment football with NO missed tackles.