Yup.What a ripoff, unfit for purpose. Vignetting like that is totally unacceptable.
I had vignetting the first time I used it. I took the filter off, reinstalled it - It slid on much easier after having been on the machine a few days. Turns out the problem was that it wasn't pushed all the way on. No problems since. Try moving it back until it bottoms out on the P3 Lens.Yup.