I'll weigh in and give an impression and share a concern:
The rubber pads are intended to buffer the metal to metal contact between the frame and the cab.
My concern is this: should the longer sections of rubber 12-14" long contact the cab and frame that to me leaves a larger area for dirt, debris, grit, and water to get caught in between the rubber, the cab and the frame; the concern being that over time through the shake, rattle and roll of driving this debris and the constant vibration would continue to abrade these areas, removing any rust protection over coats and opening the metal to moisture, further abrasion and eventual rust.
I tend to think that the small rubber pads minimize the surface area where dirt, grit and moisture eventually find their way and get caught.
I want to minimize any direct contact between any part underneath the truck as much as possible. tom
