I've been reading some of the posts concerning BOSCH 02 sensors and was wondering exactly what the problem is with this particular product compared to the AC DELCO?

I recently used a Bosch replacement and I noticed something was not "right" with how my 92 SE was running - I couldn't get to a AC DELCO replacment at the time so I put the old one back in and the car just feels like it runs a whole lot better. Is this just my imagination? Regardless, I'm going to order a new AC DELCO from GM PARTS DIRECT next week.

I'm probably the only lasting Bosch O2 user!
My 92 SE runs great with it. It might not for too much longer since I added a 180 T-Stat & Custom CAI to it though now.
I figured it had to do with engine operating temperature & the resulting exhaust gases temperature that made them fail. I believe the Bosch like the higher temperatures.

Instead of ordering from the net ask around at auto parts store and have the gm parts # and ac delco # available. Auto parts stores can often search by parts number and bring up inventory half way across the nation and will ship for free.
Often times they their computer wont even bring up a ac delco option for them unless they try the parts numbers.

I recently replaced my 186,000 miles orig equip 02 with a Bosch. I haven't noticed much difference one way or the other, at idle or full accel, but I don't think the 02 controls anything on acceleration! I do notice that the exhaust is not stinky like it was before replacement....smells cleaner (sweeter?). The 02 DC voltage appear much better too.

My gas mileage is no better, no worse too.