Admiral FCS, on 12 Mar 2010, 1:39, said:
-ALWAYS use warhead package: they increase your chance incredibly against enemy tanks. Today I killed another tank who fired first, and still had 14 HP left when the tank was destroyed.
If you see my post in the BC2 tech topic the Warhead package is only useful in a face-to-face scenario. The reload package would win out if you weren't just firing at each others front armour. Also for the Sniper Rifles and HMG, I'd choose the ACOG or RDS as they both negate bullet_drop.