If you don’t want to get stuck renting CC from Adobe just to keep current with the latest Camera Raw files, there are some great alternatives. They all can be used as Standalone. Two can be used in Lightroom, and one can be used as a plugin in Photoshop CS6. (Earlier versions of OnOne work in CS5) Each one of them you can save the results to use in even earlier versions of Photoshop, or other photo editing programs.
On1 Photos Tools
Did some price checking, and two of them cost a little bit more than renting CC for one year, BUT upgrading them afterward cost less than Adobe’s Rental program.