It really does transform the machine, and to be honest I can scarcely believe that I am using the same one. Not the least of the advantages is the speed of virtual memory; since memory limitations are a problem in the 12" PowerBook, this is an important factor.

It is said that you get more or less the same effect from installation of a fast conventional hard drive. I haven't gone that route (since fast pata drives are also expensive, I figured I might as well go the whole way and get an SSD), but it would be interesting to see comparative numbers for something like a 250GB WD Scorpio drive.