If you're going to use a gun for "home defense," I strongly suggest that you shoot it a lot, for practice and skill improvement.
It won't do you any good, defensively, if you can't hit what you're shooting at. Near misses do not stop fights.
Cheap practice ammunition is completely satisfactory, if it has been made by a competent and responsible company.
That said, I would not buy unlabelled reloads from your local dealer. Stick to known brands.
Cleanliness, in ammunition, is meaningless, because when a gun has been used, it ought to be cleaned shortly thereafter.
The difference between "clean" and "dirty" ammunition is mostly ephemeral anyway. There really is no meaningful difference.
The bottom line is: Merely owning a gun will do nothing for you in an emergency. You need to learn how to use it quickly and accurately. That requires practice, and practice requires you to shoot the thing. Often.
It is very difficult to hit a target the size of a fully-grown man from across a normal room—that is, 20 feet or less away—unless you have practiced and developed shooting skill.
Yes, I know that it looks so easy, especially in the movies. But it isn't.
Try it and see.