There are alot of ways to inspect some site for vulnerability's/fake sites/phishing sites/etc../
I use CD(Comodo Dragon) Its secure for such type of attacks.
But will be good the user to know what kind of vulnerabilitys have the site, so they can to decide what kind of information to share there..
Some of the bigest vulnerabilitys for the sites are : SQLi (Structured Query Language)/ XSS (Cross Site Scripting)/ RFI/ LFI and much more!!
BUt this can be very usefull for peoples like me!!