Alright guys, after much debate I have decided to go with the Rhyno.
Once again, thanks to Menacewarf and everybody else who helped get this thing going.
I picked the Roc solely out of popularity. I've had aces with Rocs and Buzzzes, but I keep Buzzzes in my bag.
I'm pretty sure that next year we will see a lot more unique brackets without the two big Mids in the race.