I like the wider flange AP reels for 120, but I really don't have any problems with the ball bearings. I do check them before each use though, to make sure they move freely.

I've never had success using a changing bag. If I'm somewhere where I cannot make a room totally dark during the day, I load my tanks at night and develop the next day.

I prefer stainless steel for 35mm. I would prefer it for 120 as well, except I have difficulties using the clips, and I need some way of affixing the film, because I use rotary processing.

I truly don't know how anyone could load reels wearing vinyl gloves. It might be possible to use nitrile gloves or cotton gloves - but I've never tried.

One lesson that I have learned is that loading reels requires a gentle hand - one shouldn't push or hold them heavily - fingertips are best. And the film should go on in small steps, with frequent checks to ensure that it moves freely when on the reel.

I also recommend that one listens to the sound of the film as it advances on to the reel. That sound provides excellent feedback.