Best replacement 02 sensor for 95 s14 auto

[s13pignose]

Well my car has ogne sliglhtly over the 130k mi mark, and I'm as usual trying to stay on top of maintenance. Well I've cleaned my maf, always keep oil change, new wires, plugs, etc. etc. One thing I realized that I haven't changed or that the prevous owners hadn't changed, is the 02 sensor.

I was just wondering how many are there on a 95 s14 auto (KA). I see the obvious on the exhaust manifold, but I just got done reading there's 2

Whether one or two I want it/them replaced. So what the best performing plug and play sensors, meaning no wiring?

Thanks for any help.