4Runner 02 Sensor Advice

I recently replaced the cat on my 1996 4Runner (because of rust and an
exhaust leak). It was recommended to me that I also replace the 02 sensors
on the truck (I've never done this....160000km's). Should I stick with
actual toyota sensors or aftermarket sensors? Or....is there a way of
telling whether I actually need to replace the sensors?
thanks

I went to a place yesturday to get one for mine and was told that my only
option is genuine.
[color=blue]
> I recently replaced the cat on my 1996 4Runner (because of rust and an
> exhaust leak). It was recommended to me that I also replace the 02[/color]
sensors[color=blue]
> on the truck (I've never done this....160000km's). Should I stick with
> actual toyota sensors or aftermarket sensors? Or....is there a way of
> telling whether I actually need to replace the sensors?
> thanks
>[/color]