It's a matter of opinion. Some people can't tolerate either one. I don't mind crazing, as it shows genuine age if it isn't too overwhelming. Cracks can devalue something quite alot. A hairline (in my book, a crack that doesn't go all the way through and can barely be felt with a fingernail) can devalue an article 10-30%, while a crack that goes all the way through can devalue something up to 90%, depending on how distracting it is.
Sometimes it seems ridiculous that a crack or chip an render something virtually worthless, when it's otherwise 99.9% OK. But that's how the collecting market is, and how it's always been.
