Quote Originally Posted by Ron Marshall View Post
B+W and I think Heliopan use brass instead of aluminum; so there is less chance of the ring becomming stuck...
Ignoring questions of optical quality, this is the primary reason to select filters from those two manufacturers -- avoidance of aluminum-to-aluminum galling. I once had an aluminum filter ring become permanently fixed to a lens and decided never to repeat the experience.

Another factor to consider is where the glass is set within the ring. Some Apo-Sironar lenses (and, I'm told, some newer Schneider lenses) have very bulbous front elements. My 135mm Apo-Sironar N is one of them. The only filter that can be screwed on all the way without having its glass collide with the lens' glass is a Heliopan, since that ring places its filter glass farther forward than does the equvalent B+W. I'd suggest checking each lens very carefully for front element protuberance before selecting a filter.