I've actually pondered getting an StG-44 reproduction but ultimately decided that sort of like the Winchester 1887 lever-action, it's all a bit too gimmicky. I appreciate it for the influence on the aesthetics of the Kalashnikov, but it wouldn't be worth dropping tens of thousands of dollars on a legit piece manufactured in the 1940s. In that case, just get a MG42 or M60.
The StG-44 was the world's first successful assault rifle, with features including an intermediate cartridge, controllable automatic fire, a more compact design than a battle rifle with a higher rate of fire, and being designed primarily for hitting targets within a few hundred meters. Other rifles at the time were designed to hit targets of over a thousand meters, but this was found to be in excess of the range in which most enemy engagements actually took place.
The StG-44 fulfilled its role effectively, particularly on the Eastern Front, offering a greatly increased volume of fire compared to standard infantry rifles. The StG largely influenced the Soviet AK-47, introduced two years after the war concluded. The StG's influence can still be seen in modern assault rifles, which, after World War II, became the global standard for infantry rifles.