VS vs NFS / NAT vs SNAT

I would point out that the second link is an official F5 Solution article, and while they are occasionally wrong, it is very unusual. The first link is someone's best estimate, which is awesome, but not official. The KB article is correct:

Virtual Servers trump NATs. More specific Virtual Servers trump less specific virtual servers: 10.10.10.1:80 trumps 10.10.10.1:* NAT trumps SNAT More specific SNAT trumps less specific SNAT

So from first to last:

Virtual Servers (Specific) -> Virtual Server (General) -> NAT -> SNAT (Specific) -> SNAT (General)