My audio technica AT2020 condenser microphone didn't come with a holder for a mic stand so I created one. It should fit other ones as well -Inside diameter is tapered from 50mm to 52mm. I used the other half of the old dynamic mic stand holder that screws onto the stand.
I included the .stl file and the Solidworks File
100% (Depends how much you like your mic)
Nothing special except to orient the print so the hole in the middle is on the top and bottom (so that it kinda looks like a coffee cup) and you WILL need to use supports.