DOC,
Why not just cobble together a quick test and answer your own Q? You have the infrastructure.

90% of our company uses legacy logon scripts (defined in the user's profile) and only two divisions that I know of (mine is one) uses only GPO scripts. There may possibly be some that use a combination, but I don't keep stats.
Quote:

That way I can easily modify users or groups of users to use any script I want.




Guess that depends on your interpretaion of "easy". Modifying groups of users gets a bit tricky since you cannot do group actions in the GUI and must resort to some admin scripting.
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