Originally Posted by R.I.T.Z
For a first time gun
I would suggest an electric gun (AEG)
Its a cheaper start
^This. Definitely start with an AEG before a gas system, as gas has their own unique set of issues.
If a GBBR is what you want, and you have the money to invest, get yourself an RA-Tech custom WE M4 open bolt level III. It's already been reinforced and upgraded. They also come with a flow control valve to adjust your FPS.