While I agree that the weight savings are negligible, I regularly carry three Grafmatics when doing serious shooting and find it far easier to carry three magazines versus nine standard film holders. I have not had light leak issues but I have had a few holders stuck open in the field--really a drag. They are mechanical devices so it should be expected that some CLA will needed from time to time. If that's that not an interest, then I'd avoid using them. One issue I find slightly annoying, related to the counter encroaching your image, are the boarders of the negative are not clean like with regular film holders. I started using Grafmatics when I picked up a Chamonix Saber. They are brilliant for that camera. I enjoyed them enough to use them with my standard field kit. I would suggest picking one up and use it together with regular film holders and then make a call. On a side note, I know Bruce Barnbaum uses them reliously. On a visit to his studio he mentioned to a number of us he tries to pick up used models any chance he gets.