All are perfectly for fine health wise. Infections only happed due to improper installation or mishandling, so search for a good piercer.
Here this answers the most common questions
You can pick any chip really, depends on what you want to do.
The NExT was my first chip, maybe also a payment conversion or walletmor.
@yeka has given you pretty much all the info you need, but so we can help you further
Can you provide us with some more information about the door(s) you are referring to?
Do you have photos of the door readers/cards/fobs?
Have you tried scanning the card with an app like Taginfo or similar? or are you wanting to install your own system?