Catalytic Converter Replacement

I have over 114,00 miles and now need to replace my cat converter and I have been told by the local shop that I should replace my old one with a new factory converter along with new O2 sensors. I was told that aftermarket cats are mostly made in China cheaply and may not turn off (and leave off) the "check engine light" (which also now needs replaced:). The factory part costs about $100-200 more and has half the warranty of the aftermarket "Chinese" part.
Has anyone replaced a cat converter yet? The dealer told me that they sell them for $429.71.