IMO, you must be very careful when dealing with third party resellers A big number of them are scams and always prey on buyers who are not well-informed

Blokforge.com seems legit - Here is one thread that talks about them - https://bitcointalk.org/index.php?topic=2627311 thou it hasn't been active since 2019. You can read through what different users said

As for coinminingcentral.com, avoid like a plague. So many scam accusation about them
Just type this on your search bar

I don't know about goldshell.com