You might experience some strange problems with certain hardware configurations if you use the full version but are not using any of the disks supported by its drivers. A friend whom I had recommended Acronis True Image to, was going nuts trying to get the Rescue CD he had created to work, which was crashing out to its Linux kernel screen with some bizarre SATA port errors (he has a pair of WD 150GB Raptors in a RAID 0 stripe and Windows XP Professional x64 Edition). Turns out, he was booting into the full version and his nForce 590 motherboard didn't like the disk drivers it was loading. I had him boot into the safe version on the CD, and it worked just fine.