by IB_Surfer » Sun Mar 17, 2013 3:54 am
Well, I am not going to answer your question but will give you my tale, and I think you can make up your own mind:
A while back I wanted to try a quad for big surf, had been using only a thruster. So I bought one, put in M5 fronts and GX centers in back and, well, it failed miserably in hollow big walls, the tail slipped out every time I tried to cutback hard. So I go out and buy some different back fins, Ended up with M5 sides in front and M3 centers in back. Well, that worked, but so good that it slowed the board down and felt the same as my thrusters.
So, since then I use my quad in mushy big surf and my thruster in walled hollow surf.
On a parallel line, I was watching a movie about Kelly Slater surfing Teahupu (forgot name of movie). his board had what appeared to me where size 5 fronts and some bigger size 7 backs, it totally blew me away, but watching the video I saw him drop into some incredible waves, the takeoff almost freefalling, then the board grabs and shoots sideways. I'm not Kelly, so am not going to try that fin combo, but food for thought