I actually frequently use both CentOS and (open)SUSE at work, and while SUSE is a competent OS, I still prefer Debian by a long shot. Particularly zypper has a long way to go to match apt. With that into account, CentOS provides a way stronger base, security-wise, which can be important to a sysadmin. To me it mostly annoys, though, as my CentOS system is mostly administered by the users.
Does SUSE Linux Have A Future? http://readwrite.com/2013/01/25/does-suse-linux-have-a-future