> Well, Bosch invented them, and QC of many aftermarket parts is suspect.  They
> are used in an extreme heat and vibration application, contain platinum (the most
> expensive noble metal) and quality is of utmost importance for performance, so you
> decide!  I ran the original Bosch O2 sensor on my '84 for 250,000 miles, and my '85
> has 140,000 miles on the sensor.

You can save money by buying a Bosch that does not have the factory connector and simply splicing your old plug onto it. That way you still get Bosch quality but at a lower price.  The 2.1L one even comes with a waterproof splicing kit.  

1.9L, $19.95 - http://www.busdepot.com/11027

2.1L, $49.95 - http://www.busdepot.com/15725

Ron Salmon
The Bus Depot, Inc.
www.busdepot.com