[Attitude5ire]

Iv always found having too many backends bridged together is often a recipe for disaster because you are restricted and often nagging issues come if some tweakin or updates happen and the whole system goes haywire. Personally im not a gr8 fan of vB4 CMS, its still new and the gestation period would be about 12-24 mnths before it comes any close to challenging big CMS engines but i support it because its part of a Suite. Suite has CMS, Blog and Forums all integrated under one common DB. Needs no bridging and is very dynamic.

For you to decide you just need to see whats your site's USP. Is it the content or the community. If its both i would suggest vB4 Suite because does a good job in that. Its very highly customizable, the suite is very secure and good community for Mods and Styles. Many features which often you have to add-in as a Mod or Extensions in Joomla.