[00joe]

SL has a couple full time employees building it. Also, they publish a lot of info about their build process. Centos doesn't. Sometime their releases are slower.

[keithpeter]

PUIAS Linux also has an staff team building it, and more in the way of mathematical software in their repositories.

I'm using it on a desktop at home behind a router & so I don't watch the security updates especially.

You can add the PUIAS 'addon' and 'computational' repositories to a CentOS desktop with appropriate use of yum-priorities.