I've been planning on investing on one of each of these in 77mm, for my Tokina and a few planned future purchases. I've decided on the B+W MRC CPL that is written about in the review on this site, but what is a good ND filter? I'm thinking I want the full 10 stop one for water smoothing and such, but will that be too much for waterfalls, or will a CPL do fine with waterfalls? Should I get more than one ND filter, in varying degrees? I've heard that its best to stay away from the single variable ND filters. Any input is greatly appreciated, thanks in advance.