I have a 2001 and bought it with about 70,000 miles (it has 110,000 now) almost 4 years ago-the 4.0 'shortstar' is a great engine (it was used in the Indy series races) , and other than replacing plugs, rear coil pack, and O2 sensors, it has been trouble free. Not as quick as my 96 Mark, but it is a stock low 15's second vehicle and mine is rattle free, easy to get parts for (unlike my 96 Mark-I have stockpiled 3-ECM's, 3-VCRM's, 3 sets of IMRC's since they are year specific for a 96).
Many Caddy parts interchange with the Aurora, and I can always find what I need in the junkyards. It is my wife's 'driver' and she does 40 miles a day, five days a week of city driving (stop and go, expressways/ramps) and it doesn't leak anything, has never left her stranded and is comfortable, fast and beautiful-just have to take care of it. like any other car.
Like my 96 Mark, I have a Field Service Manual, and you need it because it is not easy to work on or get info about (like a Mark). There is a couple of good forums for these cars also, so you can always get ideas on how to solve issues. My Mark came with the usual PITA issues: crappy headlights, air ride issues, parts that are hard (or almost impossible) to repair/replace (IAC, O2 sensors)-items that are easy to get to on an Olds. If you find a good example and it is in decent price, you would not go wrong buying one IMO. It DOES drive with the wrong set of wheels, but that is actually nice in bad weather, as the traction control on these cars actually is very good and it is great in bad weather/snow.
Never any trans issues either...the 4T80E is considered a very stout FWD tranny, it needs to be serviced like any other trans. I did service it when I bought it, and added a 24,000 GVW cooler, no issues whatsoever
