I am thinking about buying a Matrix m4. This will be my first aeg. I want spare batteries, but I am not sure what to get. I have found that I can get plenty of 8.4v batteries for cheap, but I also looking at this battery here: http://www.ebay.com/itm/11-1V-1600mAh-Li-Po-Battery-Li-polymer-AKKU-3S-For-Airsoft-Rechargeable-Firefox-/280956526438?pt=US_Rechargeable_Batteries&hash=item416a505f66 Also, which types of chargers would I need for each one, I am clueless, do they all use the same type of charger. And how would I put the battery in the m4. I know these are all stupid questions, but I am new to aegs Thanks!