If your mom will let you then it is always nice to snag another when you can
I don't know much about the Phormictopus auratus so I had to google it. It did not really spark my interest personally. But if you like it that's all that really matters here
The uatuman doesn't appeal to me either. I like the E. murinus a lot though but they are mean/defensive like the blue fang and hide just as much.
But if I had to choose between the two I would probably pick the Phormictopus auratus personally.
This is off topic but my Lasiodora parahybana is fast becoming one of my TOP favorites in my collection. She is super chill, big and stocky and 99% of the time out in the open. She does not try to bite but does kick hairs. BUT she only kicks hairs if directly touched. She does not kick when I open the tank or if startled or anything like that which is good. And I only know she likes to kick hairs from being touched because she did when I got her and had to rehouse her. Ever since that though she hasn't kicked a single time. I know some people have a parahybana that are pretty defensive and try to bite anything (like my geniculata - lol) but I got lucky I guess and got a sweet one.