If you are just talking about the 5,000 mah rating, then that wont hurt a thing. All the mah rating amounts to is how many times you can fire the gun before the battery is fully drained (and out of juice). So with that being said and done, the higher the mah rating the better. The only downfall that I know of is the higher the mah rating, the longer you have to charge the battery for. However, as far as I know, I think you can use a more powerful charger on a higher mah battery, but don't hold me to that.
favorite airsoft sniper rifle manufacturers: UTG/WELL
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