7
Unfortunately, I had module problems with 14 and 15. It's a tough call to make. The XOOPS devs do tend to use the opportunity to 'improve' a few things here and there with each release. Sadly, module developers are not as quick to release compatible upgrades.
2.0.16 may indeed be a better Xoops, but not if upgrading causes a critical module to stop working.
Personally, I would like to see one new XOOPS version released every year, with security patches published as required. It would give everyone a chance to actually use it.
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