STG-44 is very heavy!
I stopped at my local gun shop and they were selling an STG-44 .22 cal for about 400 or 500. I picked it up and it must have weighed 8-10 pounds! Felt very sturdy! I have heard good things about the MP5 .22 cal, and I have also held it. It is fairly heavy, it resembles the weight of the 9mm MP5 and is a very good looking gun. If you want a lighter gun, go with the MP5.