It consumes more than 1qt of oil per 500 miles, and the bores have a ton of slop in them. I'd rebuild it, but I figure a 11mm block isn't really worth rebuilding, as it seems like they have a long history of cracking. (although I do have ARP studs)
I don't think the vnt itself ruined it, but it definitely didn't help. The previous owner ran super cheap oil and fram filters for the last 200k.