If you do want to wait until you have a polished version, this may involve delaying the release date of the regular ebook. (lindsayburoker.com)
As of right now, there are no plans to further delay the release date again which is good news for everyone! (justpushstart.com)
12th March 2015 - Yesterday Slightly Mad Studios and Bandai Namco announced that Project CARS will once again delay its release date for PS4, Xbox One and PC until mid-May 2015. (onpause.org)