The Cavalier was built on the J-body. The Cobalt/HHR is built on Delta I, the same platform as the Opel/Vauxhall Astra, and Zafira. The Cobalt bashers incorrectly refer to it as a Cavalier.
I'm not a MS3 basher. The MS3 was HIGH on my list of cars to buy due to the HID headlights, LED tail...