I done the speed up about a month ago i say be careful this is for broadband users only and some pages take longer to load, one of the firefox developers recomends against doing this tweak because some pages with lots of images are slower to load and it increases the load on the cpu, since doing this i have a number of sites that are slower and some dont display properly it also causes my mediaplayer to pause when playing mp3 when the page refreshes it was fine before.
