I would think this would be best, but I suppose they want to continue offering it for some reason. -_-
Just to clarify, ZB is not based on anything as it was built from the ground up. IF is a heavily modified IPB 1.3. I prefer ZB over IF these days but IF was good back in the day but these days it's just way too dated.
ZetaBoards is more feature packed then Invisionfree and it's the successor to it by the same group of people who set up InvisionFree back in 2000. I'd say if i had to choose to use one or the other, I'd go with ZB first.
I remember back in the day Zetaboards seemed to be the more professional Choice. So i think I'd go with that
I would go with Zetaboards. There is a lot you can do with them and there are a lot of great themes to choose form if you know where to look
I started my board, hosted by Zetaboards, mid Jan and I haven't regretted my decision yet. The best part about ZB is the support system IMO.