Support - I've never had an issue with IPB support. Infact, I've always had superior results when using their ticket system. If you are trying to get support through the IPB forums, you will not get the same level you might get here on the XF forums (unless you get help from volunteers like Marcher, etc). That's because the ticket system is where support happens on IPB. And the level of shared volunteered knowledge on XF forums is above and beyond other related forums atm. IMHO, both platforms offer their own unique types of support.
Gallery - You might want to look into
PhotoPost. They have full integration with XF. However, I don't know if they have an IP.Gallery import yet. The last time I looked, they did not have one. Which is a big downfall! Especially since IP.Gallery does not currently have bulk export to download your content without using ftp.
Articles & Databases - I have yet to find anything (incl. wordpress, drupal, joomla, expressionengine, etc) that can import IP.Content data. If you don't have an issue with adding the content by hand, you can find many cms platforms that would fill most of what IP.Content currently does and sometimes even better. However, if you don't mind having two systems (IP.Content & XF), you could always keep what you have and create the forum off from XF. Unfortunately, I don't believe there is an addon for a single sign on for IPB & XF.
