If metal, the holy grail of pickups would be the EMG 81/85 pickups. Very high powered pickups and great for metal. As for the battery, yes, you'll need to install it and change it every 3-4 months, depending on how much you play. The other alternative is the new Seymour Duncan Blackouts which are great for metal as well. Each pickup should cost you around RM350, so getting a pair would set you back around RM700.