I recently acquired the 16-35mm L IS USM Canon lens. Prior I had been buying highly rated / reviewed 72mm filters. I've used several of the filter review sites prior to acquiring any UV or Polarizer filters (especially lenstip.com which was very thorough) however I am curious if anyone has (1) any experience with Zykkor or other ND faders from ND2 to ND400 or do you believe carrying individual ND filters is a better way to go? I've been told the Zykkor's use Hoya glass. I do have the Hoya ND400 HMC 72mm and the Hoya HMC ND 8 and am fond of these two but I am also keeping in mind and trying to minimize the carrying load if it makes sense. Thanks in advance.