I tried both sliding nuts and threaded rails.
I like The threaded rails a little better. It’s easier to install stuff. You just put the screws in. The sliding nuts take a little planning and some maneuvering.
The sliding nuts have one small advantage in that they slide! Sometimes you’ll have a module you’ve removed leave gap, you’ve removed a 16hp module and replaced it with a 12hp module, with sliding nuts just loosen the screws and push everything over.
The same scenario with the rails you’ll have take out all the screws, move everything and put all the screws back.
Knutlies to the rescue!