Which option is better from the following?
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AFAIK both methods will have the same result. So the real question would be if there's any particular reason to do it via a process model. The reasons for this would vary, off the top of my head though, possibilities could include needing to change a group name procedurally on some recurring basis, and/or in a utility designed to let some front-end users (i.e. basic users but with elevated priveleges) to either change the group name or change something else where the group name should follow.