I have the G36 but have yet to game or even test fire it. From my reading around, its a bit power hungry but you can only fit a mini 8.4v battery in with the hand guard. I'm debating whether to take the gun apart and rewire it all to the back and buy the G&P folding stock that fits a large battery or buy a new hand guard with rail mounts and attach a battery PEQ, which I may end up doing over the former. I had a little trouble working the wires to the rear but ended up sticking it back the way it was plus it should be a little less expensive and less work required though the draw back would be having the gun front heavy.
"Hey I'm the first one to say its a great country but its a straaaaange culture. This is a place where gun store owners are given a list of stolen credit cards but not a list of CRIMINALS and MANIACS. And now they're thinking of banning toy guns...AND THEY'RE GONNA KEEP THE F**KING REAL ONES!"
-George Carlin 1937 - 2008 (RIP buddy)