Its everything. My 2007 Impala which I just traded for the Expy had a tear in the vinyl on the drivers seat from where it creased. So cheap. .. . Just the way of the world.

Talked to a coworker who used to work at a large seat manufacturer for domestic and global car manufacturers. He mentioned that all the leather is generally the same anymore, but the seat structure and design make up, ie seams, support, contour (defined by Vehicle MFR) has a lot more to do with wear and tear than the leather itself.