They should (in theory at least), be exactly the same, since all they are is a rebuild of RHES. Whitebox is developed/maintained by 1 person. CentOS is community driven. Cent releases updates very closely behind RH. Whitebox on the other hand could take several days (or more), to put out updates. I really see no reason to use Whitebox anymore. It was a great idea when it was first on the block, but nowadays, there are several well established distros that do the same thing.
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