I'd tried DoubleSpace on a friends desktop system before and was not very happy
with the speed degradation I experienced. Don't know how much of an improvement
Stacker would be but that experience turned me off to compression utilities.

I've got Stacker 4.0 running on my aero with no problems. It takes only about
7k of conventional and upper memory. It uses some weird DPMS cloaking thing
that loads it above high memory. Works great...