This tour I have somewhere between 35 and 40 kills air to air flying the IL-2, with no losses other than colliding with a fighter I had already shot the tail off of.
Typically, the IL-2 is durable and packs a tremendous wallop. It turns very well as long as you have E to burn. A good pilot in an IL-2 is very dangerous. Many guys have not taken it seriously and paid for that neglect. The ultimate secret to being successful flying the IL-2 is E management.
The IL-2 is slow to roll, but this can be greatly improved with some rudder. It has strong elevators, however.
Nonetheless, the IL-2 is heavy and under-powered. Thus, if you find yourself dealing with an aggressive Stormovik, your best option is to take the engagement vertical. Not just a simple zoom climb. That will get you killed if the IL-2 has even remotely equal E. I mean maneuver nose high, sucking the E out of the IL-2, until he cannot do anything but get the nose down to recover some speed. That is when the IL-2 is vulnerable. Nevertheless, you have to understand that the IL-2 will shrug off snaps shots of machine gun ammo. You will have to hit it several times. So, don't blow the E you've gained looking for the one-shot kill. You probably won't get it, even with Hispanos. IL-2s can sometimes absorb two or even three hits from Osties....
The other day I was chasing a formation of low Ju 88s attacking a CV. I pulled in behind and double-checked my tail. A P-51 was diving in... I then got a check 6 from another pilot... I thought, "The hell with it, he can't hurt me", and began hosing the 88s. As first one than another Ju 88 exploded, my IL-2 was hit by fire from the P-51. He blew by, and I pulled up the nose and fired. Some hits sprites appeared and a flap or aileron came off. A split second later a 5" gun vaporized him. My damage? A few holes and the rear MG was knocked out... It's dead weight to me anyway.
That sortie I landed 7 kills, (and 3 assists). Two M3s, two Ju 88s, a Dora, a Niki and a Spit16.
Against ground vehicles, the IL-2 can kill anything short of a Tiger with guns only. I've done it many times. It takes a long concentrated burst of gunfire, but I've exploded M4s and Panzers with just the 23mm cannons. T-34s prove tougher, requiring about 200 cannon rounds. M3s and M16s need only a couple of hits. M8s, just a few more. I'll kill jeeps using only the 7.62mm MGs. Bombs only add to the carnage.
I enjoy dogfighting in bombers. I have air to air kills in the SBD and Ju 87 this tour. I'll fly the A-20, Boston and TBM as fighters too. I enjoy the challenge.
So, if you see an IL-2 stooging around up between 3,000 and 5,000 feet, avoid it. He's hoping that you will attack him.

My regards,
Widewing