Just replaced my 02 sensor today in my 91 deville. Installed a Bosch replacement because delcos were out of stock and about 15 dollars more. I have always thought Bosch to be a good brand and installed many of the parts into old hondas i have owned. So then I noticed a post that someone felt that Bosch and GM didn't get along well. Any thoughts on non delco replacements in general. I don't relly think that one sensor could be that much better that another.

There have ben problems with the Bosch platinum spark plugs, but I think the O2 sensor should be fine. Have you noticed an improvement when you put the new one in? How is the car running with it?
That will be the ultimate test.

There have ben problems with the Bosch platinum spark plugs

I've had good luck with them.

Honestly, the delco sensor I pulled had both wires fryed due to the lack of any conduit surrounding them. I had driven the vehicle for some time with them like this I suppose and performance did not seem inhinited and gas mileage waws fine. Now the engine seems to run a bit more smoothly and as for fuel economy, well see.

I've tried Bosch sensors in my '82 Eldo and for some reason it just didn't seem the same. I'm going back to the AC Delco sensor. It has a bigger tip for more air flow, so it might clog less and last longer. For some reason I think they lean out the exhaust, but I'll know for sure once I switch it to a new Delco sensor next week.

As far as the Bosch platinum plug issue, I think that pertained to a specific engine application. We poor slobs with cars older than '96 don't really need platinum plugs, but the newer systems, '96 and up require them.
If you do a search on plitinum plugs you'll get the whole skinny on 'em.
Anywho, some people recommend only oem parts religiously (sometimes for very good reasons) and some say, if it works, go for it.