I own a G&G SCAR-L and it's a fantastic AEG.
It has a stock 6.03mm tightbore, it has fantastic range, its rate of fire is good and, the collapsible stock makes it useful in CQB also.
I use only STAR mags with it and I've never had an issue. As for the battery, I use a small-type battery.
Overall, it's a very flexible gun and great for the price.
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