I disassembled and rebuilt two of these Atom 77 freewheels a few months ago. I never had any problems with their performance, but they were due for some fresh grease and new balls. The process of accessing the pawls and bearings is the same level of difficulty as servicing a Suntour or a Shimano freewheel. Hammer and punch to loosen the locking cone. After you clean the races, use Park grease or something similarly thick to stick the balls in place while you screw it back together. Best to use a pin wrench to tighten the lock cone, and some kind of thread locker on those threads. Be patient and work in an area where the balls won't roll away and disappear. I always work above disposable paper plates with a raised lip around them. Then you can toss 'em when you're done. Don't be afraid to splash out for new balls if the old ones look trashed. If you do it right it will be good for a long, long time (assuming you don't leave it outdoors year round.)
The seriously flawed part of the Atom freewheel design is the way that cogs screw onto the body instead of sliding on with splines. It's super easy to customize Suntour or Shimano freewheels, but removing individual Atom cogs is an amazing PITA and sometimes impossible. If you don't care about customizing your freewheel ratios it's irrelevant.
In my experience dismantling freewheels of different brands, Atom was the only one I have found with broken ball bearings and chipped pawls. All of my freewheels have seen decades of use and some abuse, but the metallurgy of the Atom internal components was a little cheaper. My Atom freewheels with chipped pawls worked perfectly fine despite the minor breakage. The bearings that broke managed to shear exactly in half!! There were two broken bearings in the same race, but I never heard or felt anything amiss. Replaced with fresh new grade 25 balls.
I've ridden bikes with Dura Ace and bikes with Atoms, and the build quality and design are certainly different, but the performance difference is really not as drastic as Atom's rap in the popular culture. If anyone wants to get rid of an Atom freewheel, I'll happily provide a new home.
