I was looking for cheap fun cargo vehicle. The Cruze comes only in sedan, which meant I could not get my boxes in and out of it... I brought empty boxes along on the shopping trips and eliminated everything that wouldn't fit the boxes before I even got around to driving. To be fair, I didn't find any sedans that didn't fail this test (including the Sonic sedan). The Sonic Hatchback however was astonishingly roomy for such a small vehicle, and it was also significantly cheaper than the Cruze.
If you don't need to move a number of large boxes, the Sonic Sedan actually has more room than the hatch; the hatch is essentially a sedan with its trunk chopped off. The Cruze should be even bigger... but it doesn't seem to be. Perhaps the quiet comes from added room between the exterior and the interior?