Yup, long guns in general.
I dont paint handguns, and usually not knives, although I have on occasion.
I also dont usually use the more permanent paints, as I do want the option of removing them later. I have used Brownells Aluma Hyde II with good results, and have used it as a base coat on a couple of guns. You can use the other paints on top of it, and remove them later, without the AH II coming off.
As far as prep and application, the more permanent paints require more detailed and careful prep, as well as close adherence to the directions, if you want a decent job. With things like Testors, Krylon, etc, a good degrease is usually all thats necessary.
If Im doing something for the first time, I also dont try things out on the gun itself. A 2x4 or piece of scrap of some sort is my practice or experimentation platform.
I know this isnt for everyone, and thats fine, as you said earlier, it is personal choice. My doing it has, for the most part, always been done as a practical measure, and with anything, there is a bit of a learning curve. Im no artist, and believe me, if I can do it, I would think most others could as well. It really isnt all that difficult. The hardest part, is getting the balls to do the first one. After that, look out! It can become an addiction.