Hate to say it but just because the porcelain is cracked doesn't mean the resistor is bad. Given that, I would probably replace that one just because even if it works it just plain looks bad.
I have to say that this part gets talked about lots, and definitely gets blamed for many things it can't possibly cause. Your engine may well die when it goes bad.
usually I've seen it where you get home, shut them off, and later when you go to get in and go somewhere else the engine won't start. Or more likely it will but will die as soon as you release the key from "START".
I've also seen ignition switches die with same symptoms but not as often as the ballast. (and the ballast never did die as often as it got blamed for in the first place, either )
If it blows, there's no way its gonna start up and you continue down the road a couple miles and die again.
and the one that some wiper motors have, doesn't have anything to do with the ignition.