5
Try test driving a few 'other' CMS systems out there
http://www.opensourcecms.com
I myself believe the XOOPS CMS can fullfill pretty much all your needs, but there are others worth investigating first. I have used PHP-Nuke for 3 years now, but with the security vulnerablities that pop up with it on a regular basis, to me it is not an easily manageable CMS where updates, patches etc. are concerned. I have also used Mambo, but IMO it is still too limited with the amount of addons etc. offered.
In the end, it is not your preference, but the end user on your website.
What does he/she need in order to get the full functionality from your website? What CMS is right for you and your user where management of said site and funcitonalities are concerned?..many very very good questions that only one can answer after they have fully investigated all possibilities.
Good luck in your quest!
mike