My '02S is approaching 70k, so I'm anticipating replacement of the O2 sensors in the near future. Taking a chance on generics that I'll have to rig the wiring on doesn't sound appealing, and is penny wise, pound foolish in my book.
I came across these "OEM type" sensors with the correct plugs for a very competitive $339.97+shipping for a set of 4. Yeah, they're 2x + the price of the cheapies, but they're plug and play. I have no connection to the company.
http://www.maxspeed-motorsports.com/15182.html
Gary