105s are side folders and have the same battery capacity as a aks-74u. Though 104(looks the same as a 105 but is 7.62 is way sexier! Definitly a good choice if you ever plan to do a russian loadout.
Lots of good lipo solutions for stick batteries these days.
As for brand i highly suggest lct(you wont regret it) a lct ak105/104 can be had for under 350 in canada and has none of the weak sauce potmetal cyma has
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