Auto Parts: Catalytic Converter, catalytic convertor, worst case scenario


Question
Last week, my check engine light went on, so I immediately took my Isuzu Rodeo to the dealer repair.  Their diagnosis: the catalytic converter needs to be replaced.  The cost?  At least 3 thousand dollars plus, if one considers the amount of work hours involved, which from the way they tell it, would be considerable.  

The mechanics did say that the car was still drive-able, and if I were to decide not to go through with the converter replacement, I should be able to get around.  Oh, and incidentally, they mentioned that all the other auto parts were in perfect shape--which feels like telling me that I'm in great health, except for that annoying lung tumor.  

What do you think I should do?  I've already turned down the replacement and decided to take my chances with the vehicle until it breaks down; I just feel like it would be cheaper just to wait and buy a used vehicle.  (The Rodeo in question is only barely 5 years old)  Better that than to put more money into a vehicle that just keeps eating my money.  Also how critical is a "catalytic converter" to the overall health of my car anyway?  Is this something that can lead to complete disaster years down the road--or tomorrow?  I appreciate your help.

Answer
Worst-case scenario with a catalytic convertor is they can clog up.  Only thing that will happen is it will choke the motor and it won't run properly.

$3,000 is rediculous to pay just to get a catalytic convertor replaced.  I'd find a good exhaust shop and have them do it for you for a couple hundred bucks.