I started flying the IIC back when it was relatively rare with maybe 8,000 kills per tour while the LA7 was at 30,000. I had never really considered it because, with the exception of the guns the plane really didn't seem to offer that much (OK, I'm trying to say it ain't sexy). I had several engagements against one and found out how tough it was to kill and how a well flow one could turn the tables if I wasn't very careful even though I was flying a "superior" aircraft. For quite awhile the IIC has been it's own bait, luring unsuspecting aircraft into a fight against the old...slow...low-alt target that would then promptly turn the fight around and schwack 'em. With the advent of the multiple arenas things really changed. The month after the change the IIC kills shot up to a high of over 32,000, just short of the LA7 at 33,000 kills. The secret was out.
As far as how to fight with it...well most people have covered it. You may start out with altitude but B&Z with a Hurri usually just turns into a B&..... Not much zoom potential, but then B&Z is kinda boring anyway.
As far as tips are concerned, learn to fly looking out your six. Set up your forward view to give you the best over-the-nose look since you'll be taking lots and lots of shots of opportunity, principally high-angle/high-track-crossing-angle shots. Practice your gunnery since you don't have many rounds. This is where the complaint about the plane's great guns is balanced out somewhat by lack 'o rounds. If you shoot like you're in a Niki or Pony you'll probably get one or two kills but if you learn quick and precise snapshots you can bag many more before the counters reach 0.
Learn the art of the barrel roll and forcing the overshoot. 90% of the time you'll be defensive and the overshoot is what let's you turn the tables.
For pure turning fights the only plane that has a consistent advantage is the Zeke as it's the only thing that can out-turn you. There are, of course, some others but it becomes much more pilot dependant. The F4U can be tough if he slows down. The one's that make their living fast like the LA7 and Pony are only a problem because all they do is pick while you're turning with someone else. A well-flown 109 can be tough also because they like the vertical which is tough in the Hurri because it just doesn't keep enough e to stay in the vertical with them for long.
The other thing is you're not going to run away from anything in the arenas except maybe a GV so you've got to plan your fight and recognize the opportunity to bug out if and when it occurs. Usually to successfully disengage from a fight you'll need to either kill everyone or stay alive until another friendly comes in to distract your opponents.