I can only say that I have heard through impressive photographers that B+W is the only one that does not negatively effect the image. I guess the question is, does it matter? I think that if a image is printed really large, then is the only time you will see a difference in the quality of the image due to the filter, no matter what brand you use.
I think it does matter, that would be like asking "does it matter if you use a sears lens or a canon L series lens?" If the same photo was shot with premium glass and generic glass, the premium is going to show substantially better results.
I can't see the point in spending a boat load of money on a great lens and putting a $20 sub par filter on the end of it.