Upgrade options for vb3.8.x?

I have a site running on vBulletin 3.8.x which I have closed down and intend to leave it read-only online. The only write access would be for my personal blog there (with vbblog). It has vBSEO 3.1.0 installed.

What would make the upgrade to vBSEO 3.3.2 (latest version for 3.8.x series?) worth it?

And, what are my upgrade options, seen that I won't be installing vBulletin 4 or later versions and don't require vBSEO 3.5?


TIA

vBSEO 3.5 will be working with 3.x of vBulletin once it is released as gold. Also, if you have not already I would upgrade because of a few security issues.