I have experience with IP Boards (invisionpower.com). Their software could be very powerful, but you will need to know some coding to be able to do certain things. I haven't used it in over 1 year, but everytime I wanted to do something basic, it seemed like I had to do coding. At the time I thought those features were something that should be standard with no coding required.
Xenforo was AWESOME. Look at their demo. You can request one and I think it's for 3 days. You can extend it too.
I work with vBulletin and they have too many security issues. I used to need to upgrade almost once per month.
If I was able to rank them in order, it would go like this:
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Xenforo
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vbulletin
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IP Boards
I have never used VBSEO so I can't say anything about it.
Hope that helps.