The most popular branches of Chameleon update every few days. Chimera updates every few weeks. You're probably not going to notice the difference. In fact, once you get your Hackintosh up and running, you won't have to update your bootloader ever again, whether or not you're running Chameleon or Chimera.
Just install whichever one is more easily available to you. Chimera still supports a slightly different set of graphics cards than Chameleon. [...more]