Id say its both;
I bought my 3rd w123 300DT about a year and 7 months ago from the original owner, with 143K miles. It was garage kept, and along with it came a maintenance binder a couple inches thick, which contained all reciepts from new, including many gas records! Upon purchase I felt as though i should keep her in the Garage, and refrain from using her everyday to preserve her un-harmed complection. However, the car being so nice just called and called for attention- it wanted to be driven! So needless to say ive racked up about 45K miles in the past 19 months! Oil changed religiously every 2,500 miles, and have kept on top of maintenance like a hawk, in addition to re-newing older parts that have aged beyond reliability.
The maintenace book keeps growing, and the car keeps getting nicer and nicer!
Shes just recieved a hefty rejuvination after all that service- I replced the hood pad, and had our trusty mechanic take the car and fix anything needing attention- brake pads, fan clutch, and all fluids flushed and replaced, and is ready to retire and pick up her crown as the Garage Queen. I just cant bring myself to continue driving her all of the time... I know its what these cars live for ,it would be one thing if the car had less sentimental value to me, but this is the car ive always wanted, and plan on keeping for a long time. I want more mileage award grille badges!! Call me crazy. I do!
Shes been in storage for winter, last big trip was down to LA for a week to visit some friends, including forum member Peyton300TD, whom seems to be carrying on well after losing his 300TD in an accident with his temporary 300E until he finds the next gem of a 300TD hes dreaming of.
So currently, the 300DT is driven on dry sunny days, which are few and far between, and thhe C280 has been the daily driver. I may not be the biiggest DIY'er outside of detailing and light wrench turning, but im everybit of an enthusaist as the next guy on here.
Thank god for the internet and Mercedesshop.com!