[Styrak]

Ugh.
First of all, you're not planning on buying that gun from that store, in the US are you?
Second of all, don't buy a C-Mag and slap it on an assault rifle and run around, thatg's douche-y and most of us play realistically with real mags (60-120 rounds).
Thirdly, make up your own mind about what you like, we're not going to decide for you.
Fourthly(?), don't upgrade your gun. You are new and a stock gun is fine. For damn sure don't try doing it yourself.