I've heard that you should not cook acidic foods in cast iron (e.g. tomato sauces). I use anodized heavy aluminum cookware (Magnalite Professional) for that. I do not use anything that has Teflon coating on it though. After may years of pre-scrubbing the anodized pots with a stainless steel scrubber, the anodized coating starts to wear off. After 25+ years of that sort of misuse, the inside of my pots are starting to get a bit lighter colored. The same type of abuse to cast iron doesn't seem to make a difference.
Chili is a slow cooking type of endeavor, so although I would have no problem with browning / searing the meat and onions in a cast iron pot, I would probably use one of the larger aluminum pots for the slow cooking of the chili.