The TSX & the Civic are built around to differing platforms, the former (as mentioned) around the European Accord, the latter around Honda's subcompact offering. The TSX compares more closely with the US market Accord, the EX V6 being its closet rival. The TSX represents Honda's (Acura) best balanced front wheel drive sedan to date. In contrast, the Civic EX is an upscale compact...smaller all the around when compared to the TSX. The TSX when compared to a Civic EX will be better appointed, will handle better, accelerate better, corner better, brake & maneuver better. All of this is accounted for by roughly a $12K cost difference.