Which version of Cedega to run has more to do with which games work best with which version. Which is the reason Point2Play has the capability to install one or more or all versions of Cedega so you can choose the best version to run with your games. One game may run better with 5.0 while another will run better with 4.0. Point2Play helps to keep all this organized.
Oh BTW because you're using slack and Transgaming does not have slack packages, you'll have to use the .tgz files. I'm sure this is not a problem for you. Also Point2Play gives you the option of which package to install. Although it may have changed meaning, Point2Play may automatically choose the correct package manager based on your system. Not quite sure about that last one though.