Sitejabber has 107 reviews and rating from the public pertaining to Websleuths with an added rating of 1.7 out of 5 stars (that is only 7% out of 107 reviews recommend Websleuths as being authentic).
Furthermore, some of the comments made by those sleuthed by Websleuths have included some evidences to their claims, here a few of the commenters (to read the entirety of the comments from these and more commenters, please visit the sitejabber.com/reviews/websleuths.com website)
Another Ratings and Reviews site, TrustPilot, has Websleuths at a whopping 1.5 rating (a top rating is a 5 HOWEVER every rating is only a 1 so I'm not sure how Websleuths is claimed to be a 1.5)