RE: Serenity 70W fin on a FT158?
No, I don't think I've tried that fin on an F-Type 158.
I don't have an F-Type 158, so I guess that's why.
Go ahead and give it a try, but I think the wide blade 70 is going to
work OK to get you planing early, but my guess would be that it will "top out" far too early and slow you top end speed.
Give it a try and let us know how it works....?
Hope this helps,