Of the "do-it-yourself" spray-on gun finishes, the Lauer seems to be the best.
I have no experience with it on a pistol, but it seems to have an excellent reputation on rifles, and many custom AK and AR rifle builders use it.
How well it stands up depends entirely on how well you do prepping and applying it.
Unlike a lot of other spray-on finishes, you don't bake Lauer in an oven, and it takes weeks for it to reach full hardness, although it can be used in a day or so.
Keep in mind that no where do gun finishes get harder use then on pistols.
Rifles seldom get shoved into a holster, and you usually don't sweat on a rifle. For those reasons, the Lauer "probably" won't stand up as well as a professionally applied tougher finish like one of the polymer finishes.
If you have to use a spray-on finish, Lauer is the way to go.