With your gear I presume the speed would be above normal. To keep your gear in control I would highly recommend the Select SL7 33cm, this fin is also very fast. In really CHAOTIC conditions the Select Devil 33cm will keep your down no matter what.
I have done my best speeds those days on the Is105 with a 6.3 and Tectonics Falcon F1 30... However tectonics sometimes tend to give a very loose ride, making it difficult. This is why I rode 3cm shorter, upwind speed was not that good...
I have got a 33cm Select SL9 proto for sale. This is the 2009 model, no problem to send it around the world.