This car looks great however driving it I notice poor rear visibility for backing and parking. The powerful engine is a bit too much for a FWD car, full throttle at 30 mph is a bit risky since the car darts in one direction or the other depending on the road. Replaced both hubs, no help. The fuel consumption is high in city driving acceptable on the open road though. This engine is an oil hog about a qt. every 1000 miles which GM says is normal for the Northstar, explains the 7.5 qt. crankcase. Transmission oil life sensor does not work. Plastic in and out is poor quality, dash pad warping, fender liners crack just from stones on the road. Had a rented 2007 for a month was no better.
The large trunk is excellent to carry that case of oil around the you will be needing. Full throttling the engine at low speed in 2nd gear to slow the oil usage and wasting the $3 gal gas. Smooth ride and quietness, comfort could be better.
A better engine than the Northstar could be developed. Backing sensors should be standard on all DeVilles. Put the battery under the hood where it belongs. Trunk closing lock down assist, hate slamming the trunk lid. Revive the Olds Regency of 93 and call it a Caddy, better handling, ride overall.