I'm thinking of throwing some air shocks on the rear of my lowered 58 caddy. I'm going to hook them up to a small compressor so I can raise and lower the rear of the vehicle if need be. I was wondering what the ride "feel" was like compared to a regular shock. I know they would be more stiff with higher pressure but I would probably be running with them at a very low pressure unless I needed to raise the car for whatever reason. Also, is there still oil in an air shock that controls the dampening? If I emptied all the air out of the air shock will it perform just like a regular shock?