I purchased my 2009 DTS with 29K. I have owned it for a year. I average 20K miles yearly. The car has held up well. It is a fun comfortable, fast, and pretty car. This is my 12th caddy. I have owned four new caddys and eight used ones. The used caddys offer the best savings from depreciation. I usaually purchase 2- 3 year old caddys. I put 50K miles on my new caddys and usually average 130K on my used caddys.
My favorite things about the DTS are: Northstar V-8 engine, bucket seats, stereo, front wheel drive, and comfortable ride.
The Northstar engine does not use oil like the earlier Northstars.
The front suspension could be a little more stif. and the transmission needs more gears like the other luxury cars.
I wish it had a moon roof.
Overall, I like my 2009 DTS. It has a good warranty coverage and is a good riding car. I traded in a 2000 Deville for this 2009 DTS. Quality of interior material of my 2009 DTS, although good, is a step down from the quality of material in the 2000 Deville. My 2009 DTS cabin is not as quiet as was the 2000 Deville. Front headrests in the 2009 DTS are rigid, positioned awkwardly, and obstructs rear view when backing up. 2009 DTS gas mileage is poor and the bucket seats are not comfortable for a big man. Other than the aforementioned issues, everything else seems to be okay.
Some of the feature controls (headlights switch, etc.) are half hidden behind the steering wheel. Position all controls in plain view. Provide headrests that can be adjusted (swivel headrest back) to prevent it from pushing the head forward.