buying a harness only helps improve your skills, and takes some stress off your arms. less arm movement and more (handle - brake line control) or (bar
- pushing or pulling (depowering))
there is no guideline on experience, but if you can safety launch / land and manveur a kite you're headed in the next step.
if you do buy a harness, i suggest that you fly your kite with harness in lighter than normal winds at first, practice hooking in and out.
dunno anyone on the west or east coast of canada that carries eolo / radsail .... how about HQ harness instead? or head south to
www.cobrakites.com