Honda Repair: P0420 Code, fuse box, o2 sensor

Question
My 2004 Accord with 112,000 miles had a P0420 code.  I changed the downstream O2 sensor and then the upstream one.  Still have the code.  Any other suggestions other than replace the catalytic converter?  If I must replace the cat, do you see anything wrong with using a Bonsal brand instead of Honda?  I bought it with 109,000 miles 6 months ago so you can see I don't put many miles on it regularly.  Thanks for your help.

Answer
Jeff, have you cleared the codes from the system yet 100%? Pop the hood and in the fuse box pull the hazard fuse for 30 secs to 1 min. This will reset the codes completely. If the code comes back then you haven't fixed the problem. Unfortunately the catalytic converter will go bad around this time as well which will throw the code as well.