PowerEdge Datacompression garuantee

Sometime ago we bought a Dell Poweredge. We were skeptical about the presented ratio of 1:4. We were convinced by the Dell sales manager after he pointed out the 'data reduction guarantee'. Now the compression rate it below 1:4, but Dell refuses to do anything about it as we did not fill out the guarantee form (which they never asked us to do anyway). Are more Poweredge users notice the compression rate is under 1:4? And did Dell solve it in your case?