PD Stryke bottle cage question

Just got a PD stryke kage and just read a sticker on it that says “mount kage only on frame of bike. Do not use behind the saddle”. I was suppose to use it behind the saddle and now I’m having second thoughts. Has anyone used it that way? Does it break easily when used behind the saddle thus the warning? Thanks for any info…

If it is the same shape as the Carbon Kage then it will launch bottles really easily. I’ve found that a big fat rubber band around the cage (like the ones that come on broccoli) work pretty well to prevent this on my set up, but are not launch proof.