I've worked in Illinois for 8 yrs and have not been sued yet... knock on wood. I don't consider myself overly defensive or super cautious or anything. So far it really hasn't effected how I practice.
That said, you should know the following:
1) Illinois Supreme court said limiting non-economic damages (ie pain and suffering) was unconstitutional a few yrs ago. They said it was unconstitutional, even though the Legislature passed a bill signed by the governor to limit non-econimc damges ($250k, I think). The state government on every level is basically bought and paid for by trial lawyers.
2) I have known a handful of physicians that have gotten the short end of the stick on a couple of malpractice suits. Everybody settled for something within the policy limits and I don't know of anyone personally that had personal assets taken or anything.
3) All the docs I know consider it an inevitability that we will catch a lawsuit. That said, most of the docs in my group never have (20+ docs).
4) I have for a long time considered getting an Indiana License. If I ever get a bad lawsuit, I think it might mess me up and I'd be running over to Indiana where the litigation climate is pretty close to ideal from my understanding.
5) From what I've been told the area around St. Louis (Illinois side) is worse than Chicagoland. These jobs always seem to be available. I've known people to make a killing as locums when they are getting desperate.
6) Illinois's budget situation is kind of a mess b/c of pension obligations and political infighting. They recently passed a budget and it was a miracle. THEY WENT LIKE 2 YRS WITHOUT PASSING A BUDGET!!!! If you live/work here, you have to understand that at some point either taxes are going to go even higher or services are going to be cut. Things are probably getting worse because of the recent trade problems with China b/c of how much this state is dependent on China buying soybeans.
7) I kinda learned something interesting about how these cases work in Illinois. A lot of law firms in Central and Southern Illinois don't have the means to really pull off a malpractice case, so many of them refer these cases to Chicago firms for a finder's fee. I'm not sure if this makes suits more or less likely, I just thought it was interesting.
Long story short, I think woking in IL is OK but you have to make sure you are getting paid for the risk you are taking and that you have an Occurrence malpractice policy. There are plenty of guys in Chicago that are getting paid less than 220/hr, which is a mistake. I also think a claims made policy in Illinois is asking for trouble. I think anything less than 250/hr and you have to be asking yourself if it's really worth it.
