Thanks this was very helpful.
mmanager, as for quality mags, you might want to consider Magpul’s PMags...If you can find them!
Here’s a link that might give you an idea of the PMags durability.
http://www.youtube.com/watch?v=UCFXcOOb4jc
I have several and love them.
Virgil Tripp makes some very good mags as well.
Good luck!