I love ’em too, I have 2 sets in my office as we speak (not made by me). The potential binding is just the nature of the beast. The only way I know to virtually eliminate it is to use dedicated hardware, an option you already know is expensive.
If you have the chance, experiment with the side tolerances. There seems to be a sweet spot with the right amount of side clearance and the rounded pins. Much like a drawer, either too tight or too loose causes binding while just right slides smooth as silk.
Keep us posted.
Artisan Woodworks of Texas- www.awwtx.com