Personally I loved my catera, but found that 20 mpg average for a 3.0 sucks, Cadillac parts are very expensive, and things like to break easily and often. Starting with parts, DO NOT buy from dealership, a front lower control arm will run $472, a radiator $500, etc. Always go on ebay and search for the parts you need or look online. I found a front lower control arm for $100 on ebay with 22k miles and a radiator on radiatorexpress.com for $125. P.s I love this car but am into massive subs MTX 9500's and had them in my car but the BOSE system cannot be replaced with aftermarket unless you have the entire audio system rewired, or use a rca interface like me with bad bass levels.
Bose premium sound, four heated leather seats, two front 8 way adjustable seats with drivers being memory, memory mirror with auto dimming. Very cool to play with. Acceleration even with 150k miles was amazing, REAR WHEEL DRIVE, chrome wheels, Cadillac comfort, and on new cateras rear sunshade
Flip out cup holder breaks easily, seals go bad, pricey parts, rear tail light is ok but 2000's were better without the full band, I didn't have a problem paying 3-4 dollars more per fill up for premium fuel to have prime performance and engine problems, oil leaks/overheating but I loved my Catera