Please don’t start an argument, this post is a serious warning to inform of a possible safety lack.
I'm not a Gaastra user, last Sunday a friend of mine tested a Jekyll kite and when he came back to the beach we had a look to the QR system and we couldn't open it. Another friend with big and strong hands after some attempts was able to open it, we closed it back and again locked. I'm quite sure that this device isn't sand free and should be reviewed.
I tried to inform Gaastra Sunday evening but until now no answer, so I decided to take the resposability to inform kiter’s community. If someone has a direct contact with Gaastra, please inform them to release an official answer about this issue.