I had to change my o2 sensors, (both of the rear ones only though), at around 87k, i got these
http://www.amazon.com/Bosch-15733-Oxyge ... 061&sr=8-1
You just have to wire them in which doesnt take long, and the spliced wires go in a special waterproof box, and these ones are alot cheaper than anywhere else.
I paid like $89 for both of them and shipping was even free i think.
As for people who say universal or something arent good, don't believe them as i had these since like 87k and im at 119.5k now and they have been working fine.