The film formats that are easy for me to load are 120 and emulsion in 35mm, as you just have to attach the end of the film to the take up spool, and it's easy to get it really tight if needed. Next is sheet film holders and the 2x3 grafmatics (I don't have one in 4x5), as even as you can't see your hands, it just feels natural to me for some reason. I do it in a changing bag in the basement. The film format that is a pain for me to load is emulsion out 35mm, as I usually don't get the film tight enough on the takeup spool, and it jams and binds. I don't know if there's a technique, so it winds tight on the spool, or what? Most of the time I've loaded my Minolta X370 it jams and binds, as the end of the leader isn't nice and tight on the take up spool, even though I follow the instructions the best that I can. I seem to have some luck with it, by manually turning the takeup spool gear with my thumb.