Regarding the WF I have one (15off at 34....22off sometimes skiing Mapple T2) at the begining it felt great espacially when skiing on a private lake. But since I ski 90% on open water, we have conditions changing all the time, rollers, waves, wind, temp etc... therefore at my level I went back to a regular fin because it felt more stable. I think the WF is great if you ski on a private lake and if you can have someone who can help you set up the fin correctly.
Coaching still the best investment !!!!!!