I've got a AO SA clone and it sure is a pussy cat with the .45. As a practical gun? I'd need better sights and to hack about an inch off the stock for a better LOP. Also the foregrop, the danged thing is like 13 lbs unloaded.
My grandfather carried one in the Pacific and, in the rare times he talked about the war, hated it. Too heavy, difficult to shoot precicely, and his unit mostly worked at night and didn't use guns. He did say that in the proper range you just aimed at the left ankle and let the recoil do the rest
You hear the "aim low, and let the gun go up" thing quite a bit from a lot of the old guys. Turn the gun on its side, and hold it at your hip, and sweep left to right was another.
What that comes from is, fighting the gun, and "trying" to hold it down as it runs. Another thing lot of people used to try and do to make things better was, hold the sling up at the stock, put their hand on top of the barrel, etc, trying to get better control too.
The fault with most things that try and hold the gun down is, youre just fighting the gun and its not going to work. If you relax, dont fight it, and ride the gun like it was a high pressure hose, and keep the gun moving back onto where you want it, things are easily controlled.
I used to shoot with a guy every Sunday for a number of years who had a 1921 Thompson, one of the ones with a fast cyclic rate. It ran in the 1K rpm range, and about as fast as a MAC. I dont think I ever saw him actually shoulder the gun, he usually held it "movie style", under his arm at his side, and just ripped off mags and drums, and always with a BIG smile on his face. He would also just shred the center of an IPSC silhouette target into a ragged hole. You definitely wouldnt want him "pointing" that gun at you.
Shooting "open bolt" guns, like the Thompson, M3, STEN, MP40, etc, can take some getting used to, especially if youre not used to them.
Once you get used to that bolt "traveling" after you pull the trigger and prior to the shot going off, you can actually make fairly precise and repeatable shots on things, within the reasonable range of the gun and the sights.
They also have some safety issues that need more of your attention too. Most people accustomed to closed bolt guns, think the gun is safe when the bolt is locked back, and dont realize its ready to fire. Making the gun safe is another thing you need to pay attention too. You have to remove/lower the mag before you lower the bolt, or things will likely get exciting, and not in a good way.
You also have to watch that the bolt is locked closed on safe, assuming it can be. If something catches the bolt and moves it rearward, it doesnt have to lock back to fire, just come back far enough to strip a round.
My buddy had that happen on my MAC when his hand slipped off the charging knob as he was cocking it and the bolt went forward, stripped a round and fired. Luckily, it was pointed in a safe direction, and his finger wasnt on the trigger, or it could have been ugly.