I still don't get the "tolerances" issue, as well.
As long as the press cams over hard, ALL the "play" is removed. Metal on metal, is metal on metal.
I'm not trying to be argumentative, just asking for specific facts that back up the argument.
I still maintain that, the only aspect of loading, that is done with less precision on a progressive press is the powder load because it is metered by volume and not weight.
Being able to "spot check", is not precision; but even with that argument, the LNL allows for any case to popped out of the spring retainer at any point in the loading process. As I stated, I regularly check charge weights and bullet seating depth. There is zero clearance even on the primer seating, if the primer is not seated flush the shellplate will not rotate without excessive resistance which is easily felt.
While it may be an unnecessary expense for those that load low volumes, or those that load for precision, I would never own anything but the progressive I use.