High speed video cameras are very cheap. I'd like to see more players start using high speed video for stroke analysis. If you want to improve your strokes HSV is a great tool.
BTW - the new iPhone 5s is supposed to do 120 fps.
See reply #25 with link to iPhone with 120 fps video.
Some advantages for buying a $150 high speed video camera with certain additional capabilities, zoom lens, single frame viewing, editing, etc., important for stroke analysis, are listed in the reply.