Personally I only use NTKs. I found this out when we had a Subaru that laughed at Bosch parts, only NTKs would work on it.
More recently, we purchased an 01 S60 that immediately threw a CEL after buying. Looking back through the PO's work orders, I saw he had a new cat put on the car a year earlier for the same code ( and cost $900+! ouch)... Anyways, I didn't see anything about the O2 sensors being swapped out so it was my first plan of attack. One (downstream) NTK sensor and the code vanished and has stayed away for 3k+ miles so far.