Helped a friend to repair a kite that had a small tear in a really bad spot:
These of you who are more experienced will notice that the tear is really small, but it's one of these tears that will blow your canopy wide open from a kitten's fart. And to make matters worse, it is located near a seam, so we can't use dacron or KiteAid. Our other options were either to let a professional to sew it ($$$), or to use KiteFix which I totally hate most of the time. Couple of beers made the choice really easy and here's the result:
Not pretty - KiteFix never is. But it's solid as hell and guaranteed to outlast the rest of the kite.
I have to admit that out of all products i've tried so far (outside of professional services), KiteFix seems to be the most dependable one. As i've said, it's not the prettiest one or the easiest one to work with, neither it's the quickest one to dry. But when professional repair service is out of the questions (unreachable, no time, not worth it, etc...) and when you have at least 6-8 hours to let the glue set - it might be your best option.
I really like what KiteAid is capable of cosmetically, but I have yet to see a KiteAid patch that wouldn't peel off, even when prepped uber-anally (though I can't judge about the leading-edge patches as i've sold the kite i've repaired with it before getting any real after-repair flying time).