Do you have any suggestions? I don't know any plugins that do what postmattic (pro) is doing.
I want to get a feeling for it, I want to use it and look how the basic functions work, but I cant because the devs present their plugin as "native" but then first thing you get is you need a free API key. Then it indeed does use native comment system but only with a API key, that seem as forced and unnecessary as the fact that the mail sending is not native wordpress on purpose.
I am thinking about writing a detailed review about this. Headline "Trying to Hard"