Traded in the '08 Subaru Legacy 3.0R with 75K miles for a CPO '11 IS250 AWD with 9K miles. We also test drove a 2010 C300 but wife and I both thought the car felt like exactly what it was. An entry level car.
The subaru was starting to give us some issues. Air bag light lit up randomly, a couple of weeks ago it threw codes for torque converter (sensor?) which were cleared and then came back. And oh yeah car got rear ended twice in the past year which I never fixed (cosmetic damage).
Old & New
Yes it's slow however the tech toys are fun. Navi/HID/DRL LED's/Heated & Cooled Seats etc.
I know a guy who replaced his 1.8 a4 with an is250. He LOVES his is, and it has been absolutely 100% reliable since the day he bought it (I think hes owned it since 2006 or 2007)
Although some may say its "boring" youll be laughing with the good drive, comfort, and unsurpassed(in the class) reliability.