I don’t rate either of them:
SiteAdvisor has some site information that is so far out of date as to be useless.
AVG link scanner, for me just slowed things too much (I’m on dial-up), so not practical for me.
I too use WOT firefox add-on, whilst this is much faster, it shouldn’t be used as gospel as at times sites that I consider to be good are flagged as bad and vice versa. This is the problem with community based reporting (some people haven’t got a clue), so it is guidance only for me.
WOT + Browser Defender + Finjan is better than both of all you said. I also deleted McAfee Site Advisor in my favorite as its a junk and report me only good site like bad…
None. Avasts’ webshield, in conjunction with other protection, is adequate.
I’ve never got an infection from visiting (or trying to visit) sites even when they have been reported as hosting malware.
As DavidR said, community based input without apparent oversight is pretty much a WOT
Do you mean the Web Security Guard in Spyware Terminator?
If yes I think that it is also said the be a spyware itself but spywareTerminator is a good program only the web Security guard is not good!