Originally Posted by stocky
With real coilovers, you can't go much lower than a desired setting anyway since you will need to keep pre-load on the spring.
Back to what I said before, you can adjust the sleeve lower than a lowering spring because the length of the spring is shorter, hence when you can adjust it all the way to the bottom perch, it will sit lower or as low as a a lowering spring.
Also, the springs in the sleeves are usually linear rates, although some have helper springs to achieve different rates.