System Restore is not dependable. You will lose restore points or
they can become corrupted, so your reliance on System Restore to
cover your bet is about as effective as using just a Kevlar vest and
hope you don't get shot in the extremities (head, arms, legs).
System Restore only saves *system* files (and a FEW program files)
and data (like the registry) and do nothing for user or application
data or executables; after all, it is called SYSTEM Restore, not
Platform Snapshot. It won't even rollback to exactly the same state
for many drivers, like printer drivers, so you can't depend on it to
recover when a new driver doesn't work and you want to go back to the
prior driver version. System Restore only works when some event
triggers it to save a restore point. You would think that installing
a program would trigger the save of a restore point but, no, the
install must use the new installer service to trigger a restore point
save, and there are still lots of programs that use non-MSI install
programs. One of the first steps you need to do when eradicating a
virus is to turn off System Restore and reboot to wipe all the
restore points because System Restore will save all those infected
files in the restore points. There are LOTS of MS knowledgebase
articles on what System Restore will not save or restore. System
Restore is not the equivalent of GoBack. System Restore does NOT
obviate the need for logical backups for data restores and drive
images for quick system recovery.
It might actually be a good thing that Eraser triggers System Restore
to wipe its snapshots because of reducing the temporary amount of
free disk space during the wipe
(
http://support.microsoft.com/?id=300044). If you are erasing unused
disk space (rather than erasing just some files) then you probably
also don't want to keep around those old restore points. Consider it
part of the cleanup. After all, System Restore doesn't provide
itself with an easy option to purge all those often superfluous
restore points.