I can load plastic 35mm reels in about a minute for 36 exposures. I could not load 120 on plastic in 10 minutes. I got a Hewes reel, watched the JBrunner video I found through his website, and now I can do 120 almost as fast as 35mm. I think you might have better luck with either type in a changing tent, rather than a bag, but I do recommend the Hewes reels.