Hello Les Voorhies,
Thank you for your interest in vBulletin.
I think the answer by Gaskell pretty answers your question.
I could add 1 thing on the point of security. Since most security issues are patched within 24 hours from discoevery, there are hardly any hackers that have the time to make an attack before the issue is closed. I know of hardly any successfull hacks ever on the core vBulletin product.
You might also consider asking at
www.vbulletin.com/forum where you can receive an official answer to these questions.