Radical change. The start lasted 1 minute 20, it now takes 20 seconds.
The launch of Launchpad is instant as he sometimes had him long seconds to display all the icons.
The most obvious is that iPhoto library is on the M4, launching with nearly 20 000 photos took forever before, now it has to take 5 or 6 seconds.
Even though my older machines flange because the SSD SATA I, it remains a sacred accelerator system and many applications.