Just finished some offline destruction testing with the 30mm and 37mm.
K4, Ta152, Yak 9T, Il2, Mossi, 262, 410, and 110 G2.
The bombers are tougher now. The B25 can sustain up to 5 hits before showing serious damage. The B17 and Lanc if I didn't aim for the pilots compartment, took up to 17 individual 30\37mm to completely dismantle them before achieving an explosion. The tail structures of the bombers I tested absorbed lots of damage. Cutting off wings at the root took up to 4. One to two would take off the wing tips. Fires took between 1 to 3 hits. That was kind of random across all of the bombers I tested shooting single shots from single gun installations.
One shot kills as always depended on a shallow bank landing the round into the side or top of the pilots compartment.
Depending on the fighter and where the round landed, it could take up to 3 hits to kill the fighter.
The best short burst kills on everything were from the IL2, Mossi, 410 30mm\20mm load out, 262, and the 110 G with 2 30mm and 4 20mm. The 2 30mm in the 110 for some reason shooting alone are easier to aim and hit with on fighters to 400 than other Mk108 packages.