Morfeas, study them first my friend. Then post reviews on them listing the pros and cons or likes and dislikes. Once you have your reviews up and people have them to reference and study, then you can decide on which to GM and make the appropriate interest thread/post.
Morfeas,
I got more responses for 5e Dungeons & Dragons so I am getting a campaign Running Here. If this interests you, feel free to sign up.
I still want to run some Sci Fi games and possibly have a Modern Horror campaign in the line up.
Thanks.