Sorry dude, I don't use them anymore, I just had a few sites with them, and I don't think the metrics are anywhere near worthwhile even to leave
@Nargil domain pants with a dribble!
However, I would recommend you seriously think about what you want to do with the PBNs, if you are looking to build experience and just maybe get a small PBN running and tested for cheap, then they are ok, but they rely on you using cloudflare, which isn't good for diversity obviously if that's all you have. I can never answer the question if they made a difference, as I never managed to get a spike with any link to justify that it was especially that particular link, its always a steady slow climb, as I usually do web 2.0, forum, and guest posts where possible too.
You should speak to
@Diplomat, who runs cloud IP services, if you want the real info about how effective PBNs are, as he has his ear to the ground. The point of cloud services offering IP's, it allows you to pick your host with whoever and use the cloud IP provider to get a nice separate referring IP metric, allowing you to get better IPs, or host your sites together differently and still keep them SEO effective.
Both services are similar in cost, with the cloud IP being a bit more expensive, not as easy as PBN Ltd, and yet highly customizable as you probably know even an average host can be too, and that's where although the cost is extra on top of your hosting, the value you get from a specific maintained IP is immense. You can imagine out of the two which will work better and give you a longer-term solution, but both are valid and work to their limits. Many people will host multiple domains on a single host and give them IPs via cloud hosting. It defiantly works and can be easier to maintain, as you can customize the server especially better if you are using a linux host, and also spread across multiple hosts combined. It's just really available to people who have a budget and are money-makers, as that's why you don't hear much about this type of solution compared to a cheap DIY PBN provider. PBNs are a whole other business department for me! lol
When I get the new websites that I'm building built, and indexed for months, maybe even a year, then I will start using PBNs again, until then, if you are going ahead with them, memorize the guides on BHW, and think like Google can catch you any move, and stay organized.