Combat guns and plinking guns and just having fun
I remember all of those times I spent arguing with people on gunboards about which gun was better and which guns were pieces of junk. I started out collecting many of the Soviet era military style rifles, namely the SKS rifles. There are some fun accessories from Tapco that can make even an old relic like an SKS into a more modern looking rifle, but even if it’s not an AK, you can always customize the firearm to your liking. I wouldn’t expect to use an SKS for house to house clearing, but if you got it for $200 and want to improve the fit to your liking, go right ahead.
One problem I have found with many of the semi-autos I owned was that the length of pull on the guns was very short. This was not something I go too worked up about with the plinking firearms I owned, but for a primary weapon, the rifle stocks you use on them should fit you like a glove. Customizing a firearm to fit you is an important step in learning how to effectively use a firearm. I have learned that the hard way with various rifle scopes that ended up putting a ring around my eye because the stock was so short, I forgot to adjust my bean and got a good thunk. There is nothing wrong with changing the butt pad on any gun you own to fit you. Just be aware that when you are wearing a heavy coat or winter clothing that LOP might need to be shorter, so don’t modify your stocks too much, and think about an adjusteable stock for just that purpose.
In the early 1990s there was a surplus of military style rifles coming into the Country. There were goofy thumbhole stocks to avoid violating gun laws or cheap parts for kits. Many of these rifles had pretty ugle stocks especially many of the rifles coming in from China or Egypt. If you have one of those MAK90s or Maadis that works great, but looks like crap, you might want to upgrade your stock with a synthetic. Many of these stocks are made in the US and can be considered US Parts to add to your legal alterations of your gun.