vBulletin vs. PHPBB

Obviously price is an issue here, but out of curiosity for those who have tried both, are there notable differences for a low volume bb system (this won't be a 20k member bb, more like 100-300 member information source)? Major failing points, glitches, support issues (obviously with open source I don't expect the moon but...) etc? Any help or feedback would be appreciated!

 

A sieve meaning the security is not impressive? For a small members only site, you expect it would be majorly problematic or just bad if there is necessarily secure ? Any other open source code bb stuff that would be less problematic, or do you just recommend ponying up for the vBulletin? Keeping in mind paying anything to get this up and running is NOT something I want to do right now, and if the security is a little lax, but it functions properly, I'm not as concerned...is that the biggest headache or are there more you didn't go into?

 

Limited in terms of? Sorry to be pedantic, this is something I'm really not familiar with in terms of what you can and can't do. It's a bit difficult as I can't really explain what I'll be doing, but expect maybe 3-5 "sections" with probably 50-100 users for the first 3-6 months, and maybe up to 500 at full tilt...I really don't need much in terms of extras; one of the reasons I thought the open code might work for me...