What is better, PCI card or usb for wifi?

Got a new computer. Previously was using USB and it's done me well. However now I want the internet on both so I'll be saving the old wireless adapter (USB) for my old computer. What is the best to get for my new computer? I'm very close to the mobile hotspot (2 feet). I could plug the hotspot staight into the usb but when I do that it randomly shuts down and resets so I'd rather leave it plugged into the wall and get a wireless adapter.