I've been using a 9.6V G&P 2800 mAh "brick" battery mounted inside a PEQ box for a while (3 years). No complaints at all. Not sure of what the internal battery is since this one actually came with the battery sealed inside the PEQ but I would assume it's the OEM G&P battery cause that would only make sense.
ಠ_ಠLess QQ more Pew Pew
READY TO >> RACE