Brian, I've had a VFC M4 gbbr for a little while but haven't had the occasion to field it yet. However I have a few questions; Is there a place or a thread that talks about the compatibility of parts?
For example I'd like to get a railed front end but I'm unsure what fits with what. Am I forced to go real steel or I can still go with airsoft parts?
Also, does any of you play with CO2 magazines? Are they good or propane mags will do just fine?
Thanks alot.

I have an AEG and my GBBR and would sure love to switch and use the GBBR as my primary and the AEG as my backup. It's just that I'm not entirely familiar with the GBBRs yet...