Thanks for the feedback guys ...

I'm quite interested in Invision as well, as their product seems very slick and they offer lifetime upgrades and support for a once off fee (yes, it's not free software ). And they have other products such as a gallery which integrates straight into the forums - so that could be very cool indeed.

However, Invision don't have a converter for punbb (yet). Although perhaps I could go the long way and convert to phpbb and then convert again to Invision.

I'll probably set up a few test boards of Invision, vBulletin and Phpbb, do a test conversion and play around with the features to see which one suits our needs the most. When that happens I'll invite everyone to hop on to the test boards to have a play around too...