Hi gurus,I read many thread of SEO services(most are link building sub-forum), found most reviews posted by large quantity of different clients in these threads were positive, some of the services maintained a long time, e.g. from 2012, I'm very puzzled because so many people said: "do not use black hat SEO for your site", why so many webmasters still use them and satisfied? Did they all run a short term website? For instance, build a new site and use service here rank some keywords in 1-3 months and get some orders, after some weeks the keywords are all dropped, then abandon this site and build another new one, and rank keywords.....over and over again. The following pictures are posted in some other forums,please see and give some advice here, thanks.