That's why during my first period in WF, when I didn't know many things on SEO I preferred people providing high priced products and having positive testimonials. I ordered two services which were priced much more than the average $17 - $37 that the majority of SEOers ask. For different reasons I got 1/100 of the links promised, most of them from PR 0 sites and with no real seo value. I also saw my sites ranking fall instead of raise!!!
What I learnt out of this period was that positive testimonials are not enough, but it is very important who gives these testimonials. The majority of those who gave these testimonials were people who were also newbies in the IM. Few more experienced IMers were posting some questions, and seemed to make payments for the products, and since that moment were lost: no other reply or request from the service provider. Probably they were satisfied for the services, or asking for a refund, without spending their time for a negative review. At least, that's what I thought at the moment.
There is a problem with SEO that makes all these people survive, instead of the fact that they offer nothing. Using an automated product that produces link wheels, blog comments or any kind of links, doesn't ensure that the buyer will outrank his competition and achieve a spot in Google page 1. Just watch the last pages of people providing these services and you will read a lot of answers claiming that the competition was too high (are there really any keywords in any niche with low competition left? and if there are, why all these people do not make an estimation from the beginning?)
I did a case study on this: I asked someone to make an estimation for a newly created site, providing him the keyword "internet marketing" :-)
Before him starting working on the project, I asked him to tell me if the site could be in the first page of Google. He didn't reply, but send me report of the backlinks he created (useless rubbish with no real impact to my site ranking) and when I asked for a refund he told me that he should be payed for his work (!!!), that he didn't promise a first page spot for this specific keyword (!!!!) and that he would keep working on providing backlinks till this keyword achieves 1st page (!!!!!) -competing sites with more than 10 years Age!!!
I didn't ask for a refund to see where he would go. He actually let the time pass and I saw my site getting no links through Market Samurai.
Having acquainted some good experience in the field and being able to conduct my own SEO to support my sites, I just want to end by providing some guidelines to all people seeking to buy some SEO service:
1. Do not expect to be in Google first page with the SEO service you buy, no matter what the seller promises.
2. Do not hesitate to submit all your questions -BEFORE YOU BUY- even the silly ones. Forget the guy who doesn't reply or is rude/arrogant/uninterested. It's not because he doesn't have too much work, but because he is not a good professional. Don't get a product that you know nothing about.
3. Try to learn some things on the product you will order. Don't pay for a link pyramid if you don't really know what this means. Even if you believe that it is something good, or something that almost anyone does, if you don't know what it is or how it could help your site, leave it. Do some research and when you know the answer to these two questions, choose the best service that may match your needs.
4. Do not prefer people who promise to do the whole work for you and get your site to the first page of G. If they could do this, they would do it for themselves. Give priority to people offering specific services that really match your needs.
5. If you pay for backlinks remember to ask where they will be added, if they are dofollow and what is the PR of the sites where they will be added. If you really know nothing about SEO, just order a package of high PR backlinks.
6. Remember that if you buy a package now, you will have to buy similar packages every month, as Google ranks high sites with a regular link raising. So, create your backlinks like playing a strategy game, or, even better, a chess game.
7. Spy your competition (I'd highly recommend Market Samurai for this purpose, although lately even this has some serious issues which are to be solved), and try to outrank the number of backlinks that they have.
8. In case you make a good report on your competition, consider "copying" their backlinking strategy. Get backlinks from the same blogs/sites they get their own.
9. In this case, you could create backlinks to your site on your own, or if you don't want to spend the time go to odesk find someone from Kenya, Philippines, India etc. with a moderate knowledge of english language and ask him to make some blog comments with some anchor text links back to your site.
10. Ask for a report. Personally, if a report is not added, I cancel the whole order. In case your backlinks are never indexed by Google, you get NOTHING -even if you pay $5, which is the case with the majority of useless SEO services provided in Fiverr, and which get high rates from people who don't know what they pay and what they get!
11. Do not hesitate to ask your questions in the WF for anything that you want to know. There are literally THOUSANDS of people here who will be willing to answer your questions.