here in germany, mny kiters use homemade quickreleases.
a good system is a snap-shackle (the shackle made by 'wichard' has proofed to be the best) mounted on your harness-hook.
one pull and you're rid of the kite.
or the chickenloop made by flysurfer (
http://www.flysurferusa.com)
works well, too.