How much pressure should be on the magazine release? should magazines insert easily or with a noticeable click?
Mine takes about 4 lbs to start moving it and about 8½ lbs to fully depress it. 10 to 11 lbs is required to start a magazine under the undepressed catch and it does go "click" when fully inserted.
And, if you really want to check your catch spring, there's a blueprint of it in our Tech Issues section with dimensions, springs rate, etc.