Following on from Snips' response, Powerline plugs would be a good way forward.
However, if you are looking for PCIe vs USB, I would say it depends on the quality of the wireless product. If you spend £60 on a USB reciever, I'd say it would be the same quality as a £60 PCIe product. But at the low end, I think PCIe would be best. Anything with an external aerial in honesty should be ok.