Which Circular Polarizer

My boss is buying me a circular polarizing filter and has given me the choice of 4 brands. If you had to choose between a ProMaster Nikon C-PL-II, a Sony filter kit, or a Canon filter. Does anybody recommend one over the others? If so why? The price is not an issue for them just the quality.

Thanks for input.

Jeff

I have a Promaster and it does the job.

http://gallery.photographyreview.com..._7334_w640.jpg

Some may argue that if you have a VERY expensive lens, you should not use a cheap filter that will degrade the quality of the lens. I've read websites showing evidence of this.

Thanks for the input. Anybody else have thoughts on this subject. I need to justify the additional cost of the ProMaster or be able to say that the Nikon and Canon are just as good. Please I need more input.

Thanks,
Jeff