I like the individual holder bags that Quality Camera (Atlanta, Georgia) sells on eBay, MC Gear brand, about $30 each for 7x17. They are light tight, Velcro sealed and padded. I washed off some mud I had gotten on one and discovered that they also shed water. Dick's Sporting Goods sells a light weight back pack for about $40 for scuba gear that nicely holds six holders or more in the bags. I use a baby jogger and this back pack fits nicely on the frame rails. Bungee cord keeps it in place. The weight helps to keep the jogger's center of gravity low. Young mothers in the park get very upset when they see an over turned baby jogger, especially with an old guy driving. You hear them mumbling about never trusting a grandfather.
John Powers