Some of the worst things I've ever purchased in my life. Awful product. Bought 4 of them. 3 of them are in tatters, the other looks ok, but still not perfect, and that's only because it's the one which doesn't get used. Exceptionally poor product. Clearly a design issue as everyone complains about the same experiences.
I must be honest, when I wrote to complain, they were willing to discuss, however as they said I'd fitted them them to Keylite Fixed-Shut Windows, rather than the opening ones they are designed for, that they wouldn't consider them under the guarantee. They do not however make an option for the fixed shut windows so I had no choice. I was told when I bought them, that these were the only ones available.
If the experience I'd had was just me, I'd agree with them, I shouldn't have fitted them to these windows, but what's happened to mine has happened to everyone else's. The blinds pop out of their runners, and have now torn / frayed.
I had no real issue with the customer service, they were responsive (although not positively!!), but the product is complete rubbish.