I still have and use Vietnam era magazines, some still have 1970's mud in them. They mostly still have the original aluminum, non "improved" followers. They never have issues. I have never needed an alibi at a match due to my stuff not running. 35 plus years with AR style rifles, never saw a need to fix what is not a problem.
These AR's are great due to how lite and nimble they are, but I do have to say that nothing beats the feel of wood and finely machined metal in form and function. I'm still waiting on my mags to come in, but have a feeling I will prefer the feel and solid contact of the Gi's, appreciate the lightness of the pmag, but look at them more as disposable.