Oddly enough, I think it is about 5% of their gigs that are legitimate, genuine and original services that do what they say they will do and actually be of value to you.
I have purchased 3 different traffic services all claiming to send "Real Human Traffic".
Of the 3 that I purchased, 2 where absolute total scams which where sending bots to the site and one of the sellers was so blatantly arrogant he was telling me to not use analytics and instead to check my server logs as analytic's is the worse traffic tracking service!
I swiftly cancelled and reported him and the other seller to Fiverr's support.
The third like a diamond in the rough however has actually come to the table with real human traffic as promised.
It might not be the best traffic (buyer traffic), but at least it allows me to test what I want to test which at the moment is the stickiness of the posts, bounce rate, click through's to links and banners etc.
Dont give up on Fiverr just yet.