While I own a Lock N Load progressive, I recommend and use the RCBS Lock Out Powder die because it locks up the press for an under or over charge. Since I got it, it's locked up a time or two when I screwed up operation of the press someone fiddling with something.
The Hornady one is "ok," but I think RCBS has the better product of those two.
Another more expensive option is the Dillon powder charge alarm system which can be adapted to the Hornady, as can the Dillon powder measure with expander dies, if one so choices. (Note: The Dillon measure works very well with pistol powders, appears to be a little less expensive than the new Hornady CAPD and already has an expander for .30 carbine.) and can be adapted to the Hornady using the springs the Dillon originally was designed with, part number 14036, you'll need two.
Hope this helps,
Dave