I'm incredibly biased towards iB, since I've been following it's development sice it started. The current betas are quite stable, and a lot of people already use them as their main boards. They haven't released a specific release date for the final "Gold" iB, but I'd say it's close (maybe a few weeks).
iB uses the DBM module, which is somewhat faster than flat file and like I said, they're also planning on releasing MySQL support shortly after the Gold release. If you need an idea of just how fast it is under high traffic situations, just browse around the
official support forums. Bear in mind though, the site has
mod_gzip installed.
In the end, it all depends on your personal preference. I went with iB because I thought it was the best free board available to me and I don't have PHP/SQL available to me at the moment. I don't really see the point in paying for a message board, not with all these freebies around
- Mark
Astro-Boy!!
http://www.zip.com.au/~astroboy/