vb, bbpress or smf? and which hosting?

Hi

I am on dreamhost at this time.

I'll be launching a forum soon. Wanna know which one I should use?
vBulletin, buddypress or smf?

Also is dreamhost ok or should I go to mediatemple?

I can't answer the hosting thing, but as for the programmes, if you are willing to pay vbulletin is the best, there are other ways to get it but you could be closed down for it, if I don't know buddypress, and SMF is the best and easiest free one to use, I currently have a forum using smf and it looks really nice. There are some nice themes out there for it.

But i will say if I had the money I would buy vbulletin.

Thanks a lot for feedback. But I think that vbulletin is old. Money isn't an issue. What I need is

1. A Search engine friendly permalink structure, which can be done in any forum software.

2. Fast.

3. Don't consume much server resources.

4. I can customize it easily. (I know PHP well and I am wordpress developer)

Can anyone tell me from his experience about which one of the forum is fastest and consume less server resources.

Also, I just came across to mybb, described as the free vbulletin. Do anyone have experience with it.