I purchased my '01 SES 24v in September of '02. I have had amazingly trouble-free miles (148k currently!). I upgraded the springs/struts (that was a personal choice), but other than that, nothing major has gone wrong. The key to these cars -- any car, for that matter -- is to perform maintenance on schedule religiously. I have reduced the transmission fluid interval to 20k, as these transmissions are a known weak spot. Around town, I drive this car with the transmission in Drive, not Overdrive, and that seems to have made a big difference in the performance of the transmission. The Duratec motor (24v DOHC) is far superior to the Vulcan (12v SOHC) in both performance and mpg.
24-valve Duratec engine, exterior design (especially with the trunk spoiler), amazing reliability, durability of the paint (though mine gets frequent detailings). Also love the 21+ mpg around town (at 148k on the odometer, no less!). Even better, it starts when I turn the key!
4-wheel disc brakes, better quality plastics on the interior, dual-exhaust setup with bumper cutouts, upgraded leather quality, gauge package instead of idiot lights, bigger boost in power from the V6, 5- or 6-speed auto or manual transmission would be a nice option (as it is on the 2010 model)
† Edmunds.com received the highest numerical score in the proprietary J.D. Power 2014 Third-Party Automotive Website Evaluation Study℠. Results based on responses from 3,381 responses, measuring 14 companies and measures third-party automotive website usefulness among new and used vehicle shoppers. Proprietary study results are based on experiences and perceptions of owners surveyed from January 2014. Your experiences may vary. Visit jdpower.com.