G&P 3000rd Auto-Loading Ammo Box for M249 Airsoft AEG Machine Guns

"Pros

1.) Good battery setup, lots of room for bigger batteries to power the box mag and gun
2.) Holds 3k bbs
3.) Can easily take apart box mag for maintenance

Cons
1.) The auto winding over winds alot
2.) It doesn't matter if you shoot 3 bbs or 25 it will over wind for 3 extra seconds causing the box mag to over wind.

3.) You need a hpa engine set at least to 20 to 25 rds a seconds to be worth while.

4.) If you do not shoot faster then it's reloading your gonna break the box mag and gears due to over winging.

I put a lot of emphasis on over winding :)