For what it's worth my 2000 4.0 has just 2 sensors (no mini cats), and I used Bosch and they've been fine.
Glad I read this post. How long have your Bosch sensors been in?
I just replaced the exhaust system on my '97TJ, from (cracked but welded) header all the way back to the exhaust tip. We put the original sensors (yes, nearly 15 years old and never had a problem) back in, and two trips later they started throwing codes.
First time it happened I got a P0135P and a P0138 (no P). The MIL had lit just after it ran a little rough. BTW, what does that second P mean in the "P0135P"?
Reset the codes (with code reader).
I checked the codes again this morning after coming in to work, because I got a rough run pulling out after the engine had been running about 2 or 3 minutes. No MIL light, but I checked anyway, and got a P0138P.
Anyway, I've got the 1/1 and 1/2 Bosch sensors but haven't installed them yet -- although now I'm wondering if I need to check the part numbers against this thread before I try to install them. Or even trade them in on a different brand, although after reading this last post, I probably won't unless the part numbers are wrong.
I was hoping it would sort itself out after the "newness" of the pipes burned off, but I'm guessing that isn't going to be the case.