We use the Scim's and 3/2/1's in the Natural Composite most frequently. We have the 3/2/1's in a clear hex RTM and I'm undecided on those. They almost feel like they aren't foiled the same the Natural Composite based fins. We also use the F4 437 in Black Stix 2.0 construction. That's a stiff fin.
I've been wanting to try something in the black tip soft flex construction, but haven't found one in a template that I'm willing to spend the money on.