I've had my 300 since it had 2500 miles on it, it now has 55,000 and I've never had an issue with it. The only expense I've had is oil changes and tires. It's not as nice as a BMW, Mercedes etc. but you will not have to pay for costly repairs. Again, is not as smooth a ride as other luxury vehicles or as nice, but not having the head aches make it worth buying.
The exterior, it has a beautiful body which can be modified if you're into that. From wheels to Grills, you can make your 300 look as nice as you want.
Interior needs improvement, it looks great on the outside, but once you get on the inside you realize you're driving a Chrysler. If they could make the inside as nice as the outside they would have a perfect vehicle!