Genocidicbunny
Bug squasher
Ah that helps and for level 4-1 try to stay in one spot where you are comfortable, dont run all over because while you are trying to kill those little shooter robots the helis get you and just dodge every bullet that you can unless you can get a critical shot in. Oh and pray that you get a good weapon or like you said that the cheat affects percentage, use it for the wanted weapon. Tip-dont try to use the abomb launcher until the last heli or so because then you probably shouldnt care about getting hit. I say this because the damn thing is so slow I could probably kill the heli on my own before it hits. So otherwise pray and use all the skills youve got because 4-2 and 4-3 are hella harder, believe me.