The Tata Harrier and Sierra are both in different segments, but with the price and even feature overlap, we can understand your dilemma. In terms of engine performance, the 1.5 L Kyyojet diesel is basically the same unit as the 1.5 L diesel from the Curvv and Nexon, thus in that sense it's a proven unit. As for refinement, both the Tata Sierra and Harrier engines are vocal units, the Sierra being slightly louder of the two. If your usage is mostly in the city, the Sierra would be the better of the two. It feels lighter on its feet, and the smaller footprint will be easier to manage in traffic. Furthermore, the Sierra sits in the 'right-size-for-India' space; it's just right for our tight and dense traffic, but also large enough inside to offer good room and comfort.
