Overall quality is better than a mercedes. The cars power is very smooth and linear, no lag when stomping on the gas. The ride is fairly rough, but I guess that can be said with other suvs i've driven in also. Normal driving, it feels like an suv, but when you push it a little through the curves, it behaves like a smaller car. I like it a lot, I've test driven the ml63 and the x6m (no x5m on the local lot) and this car feels the most planted when pushed. Interior space is good, but the cargo/trunk area needs to be bigger.