You would be wise to resist getting a newer car. I gave in and traded my 2005 Park Avenue with only 41,000 miles for a brand new 2011 Lucerne. I have had some minor factory paint defects that have really completely ruined the new car buying experience. I traded the car for well below what it was worth, and I actually liked it better than my new car. I am really kicking myself, and I'm already considering getting something else after I get my tax rebate check next year. The new cars just don't compare to the traditional old Buicks.
Update: I'm now at 197k and the car is still alive. I've had to do a couple of things.
I've changed out my heater control valve; it was plastic, and just broke one day, and spilled coolant everywhere. It made my serpentine belt slip off, but I was at home, so no major problems.
I had to change out my alternator yet again, but purchased another brand this time.
I also had to change out my harmonic balancer; it went bad.
I installed a new fuel pump replacement for peace of mind.
My A/C is acting up yet again, but still blows cold air. I will just deal with it at this point.
This round of repairs cost me around $400, which isn't too bad. $0 in repairs would be nice, but the repairs are still cheaper than car payments. I plan to keep my Park Avenue at-least one more year, and hopefully make it to 200k; it seems that it will. It's been a faithful car overall, even though it has caused frustration at times.
A/C has been my major headache, and the most costly repairs.
Update: The car has around 205k miles now. It's no longer in my possession, a relative has it. I have now moved on to a 2009 Toyota Camry SE, which I do enjoy.
Only minor things have occurred for the most part since I last posted. A battery cable and few issues with the fuel line have been the only problems that I know of, and it's in need of shocks; they are past their time, and I think the water pump has a slight leak.
Cosmetically it needs another paint job, and the roof liner has finally began to drop some. Still purrs like a kitten and shifts silky smooth with 200k+.
I am very surprised you are satisfied with a Camry coming off of a 90s Park Avenue. Those cars rode SO smoothly. Personally I would never drive a mid-size Japanese car, but to each their own. I hope it serves you as well as the Buick.