phpBB User Looking to Convert

I am the owner/admin of several large forums that are running phpBB2. Currently, speed performance (and always being scared of being hacked) is my biggest reason to move to VB.

I have 2 questions:

1) I know this is tough to ask since it has a lot of variables, but will I see a performance boost from phpBB2 to VB/VBSEO?

2) My site urls are www.mysite.com/forums/viewtopic?=####.php

I never claimed to have rewrite skills, so would it be possible so all of my old threads redirect to the new VB path?

I have tens of thousands of indexed forum pages in the SERPs, it's just to valuable to lose.

Thanks for your time.

2) Yes, there is a script available here which would allow you to redirect all the old phpBB URLs to new vBulletin URLs.
Take a look : 404 / 301 Tool After Import Redirect on ImpEx imported forums

1. You will see a DECREASE when you first convert over. Give the spiders some time to go through and re-index everything and you will eventually see a dramatic increase.

If you do decide to purchase vb and vbseo, be sure to look over all the guides (especially briansol's guide to vbseo) before you start installing anything so you can get everything ready prior to installation (less downtime ).