I have a Hoya - actually a few Hoyas - and have been very happy with the quality vs. price. B+W brand filters (made in Germany, not specifically for b&w photography BTW) are pretty much regarded as top of the line but can be very expensive. Better polarizer filters will also be more "neutral" in color, where it's possible that lower quality filters may add a very slight color cast. I have to believe that this won't be noticable to everyone and certainly not in every situation, but be aware of it. With polarizing filters, you generally do get what you pay for.