how would you guys rate them in terms of effectiveness?

The landboarding one is absolutely brilliant very concise goes over movements a few times AAAA+

For Prog. Kitesurfing, make sure you get Volume 2, the updated one ...

as an intro into the sport its good. if your are a harnessed rider already it's boring but with good board control tips and balancing points.

self discovery and time on the kite in the water ...there is no substitute.

you must have total confidence on safety measures for yourself and others.

weather, water, wind and sailing...comfort and knowledge in these areas are essential and typically understated.

then it just a matter of time