Time to replace my 02 sensor (upstream) is there such a thing as a high performance 02 sensor and if so are they worth it and should I replace both at the same time.

My mods include a HKS filter adapted to the stock intake pipe and a tsudo 2.5 catback exhaust

Just get an OEM replacement. The only high performance O2 sensor that's worth it is a wideband, but you can't really replace your narrowband with it, and it doesn't add any performance, just better engine monitoring.

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http://www.dsmregistry.com/detail.php?carid=1133
*form follows function*

the OEM (mopar) o2 sensor is high performance in that it will last much longer that typical autoparts store replacements.
like Bosch o2 sensors have been known to go bad in as little as 3 months, when my mopar o2 sensor typically lasts 4-5 years.

1998 dodge avenger 4 cyl AT
Mods are:
Not enough

I dont know what you guys are doing to your O2 sensors but mine is still OEM and i have 150,000 miles on my car never had to replace it yet (now that i said that it will break), anyways just get the OEM 02 sensor.