The only "failure" of One Shot is some difficulty in knowing whether the spray left lube, or FAILURE TO SHAKE THE CAN ENOUGH led to only the propellant getting on the case.
I find One Shot to be a bit the opposite of the Dillon lanolin-in-alcohol spray. You HAVE to go light on the Dillon or you'll get shoulder dents. You HAVE to go generous with One Shot. Don't stop too soon at the edges of your pile of brass. It also does not "run" around the case quite as well as the Dillon stuff, so I prefer to line my cases up and make sure they are rolled over for a second spray.
All this is worth it to me, to avoid the case dents, the gummy buildup on the shellplate, and the sticky, gummy mess that I have to clean off the loaded rounds. I prefer to not generate gummy media in my tumbler, so I still drop them on a towel and spray them off with carb cleaner. One Shot gives me more cleanings per towel, fewer sprays per cleaning, no gumming up the cleaning towel, and no "oops, thought they were clean but now they're sticky" feeding troubles with my semiautos.
With the X-Die, it *will* work best if you trim the cases as instructed. I do that after the first reloading. Part of why I love my once-fired brass--just load it and go.