For the record-
If you choose the 6 gun heavy loadout, you might as well take the 8 gun light. There's barely any differene.
HOWEVER
A p47D-11 at 25% gas, with the 6 gun light option is damn near a spitfire. It's a COMPLETELY different monster.
You throw the P47D-40 at that loadout and suddently you've got a jug that'll challenge a P-38 in vertical maneuvering- no lie.
So.... what does this mean?
If you're upping for a short range base defense furball twisty-turny-hair-on-fire thing, take the 6 shooter light. It's a LOT of fun.
If, however you're going to do what the Jug was meant to do (either sweep the skies clean from enemy fighters from a position of advantage, or flatten the nearest small metro with your ordanance), take the 8 guns. it's what driving a Jug is all about
8 Gun heavy I've found useful for bomber intercepts/hunts. Normally, however, I'm on the 8 gun light or the 6 gun light.