Is the Moz Spam Score a reliable detection of PBNs?

[Avid-Panda]

Hello Moz community

I am looking at a couple of websites to guest post on and it feels almost too easy. I am concerned these sites may be part of a PBN. Their spam scores are quite low however (6% - 11%). Is the new Spam Score on Link Explorer (not Open Site Explorer) a reliable tool to vet PBNs?

I asked a member of the Moz team but they didn't know. Perhaps another will.

Here is the website http://www.dspacecloud.org/

Thank you in advance for your opinions.