I'm going to get a polarizing filter as my first filter and am not sure if I "need" a slim filter. I have a 77mm normal lens but also have a 72mm UWA. I understand slim filters can cut down on vignetting at wider angles, but that if I'm shooting with a 11-16 lens (vs my 17-50), the effect of the filter won't be uniform at such a wide focal length. I will probably get a B+W Kaeseman MRC, and the price difference at B&H isn't extraordinary ($3). I guess the only other thing I can think of is that I wouldn't be able to stack filters onto a slim filter, but I am not sure if I would see myself needing to do that anyway. Any thoughts?