Toyota Repair: Oxygen Sensor 1999Toyota Avalon, toyota avalon, oxygen sensor

Question
Ted,
I have a check engine light on my 1999 Toyota Avalon (70K mi). The tech at Autozone read the code and said that the oxygen sensor on the front of the engine is bad.  They have an OEM replacement for $189 or a universal for $69.  They said that the universal might not make the engine light go out, but anothe parts person said that he had never known a universal O2 sensor to fail to make the engine light go out.  What do you think?  

Answer
I can't comment because I have no experience with aftermarket 02 sensors, it sounds a little strange that they would sell a part that may not fix the problem and even stranger that the employee would make a statement like that, there should be some sort of warranty on the part if it doesn't fix the problem.