Haven't tried Boonex. I looked at it, looked comprehensive, but wasn't hosted so I didn't go any further.
I tried Ning, it has lots of features and they all work, but I canceled my subscription with them after a few months. For me, the biggest problem was that their SEO didn't seem that great - Google wasn't that into the content. There could have been a lot of reasons for that (it was on a sub-domain, the urls weren't great, lots of extraneous links on each page, etc.) I started to dig into it but I wasn't that motivated because IMO it also has _too many_ features. The base product is a bit busy, and it is hard to turn most of the features off or blend it with a larger web/mobile presence without getting a developer involved to create templates, etc (and not even then, in some cases). Of course, if you want all those features and don't care that much about SEO, etc., then it's awesome. FWIW, they didn't refund the balance of the annual subscription...business is business, but it seemed a bit lame since I gave them a fair bit of constructive feedback.
I am currently using BuddyPress and BBPress on a WordPress site. Simple and clean interface, well integrated, easy to find plug-ins or developers to tweak it, and so far the SEO results on the user generated content are much better.