Most of the time the update process using Update Manager works without mishap. However when it gets hung up it can make your system unrecoverable. I find the on-disk recovery tools worthless and the Image backup tools, that I am aware of, also not producing a bootable result. They are so cumbersome to use that I probably am not using them right. I wish PowerQuest’s Drive Image product had continued to be developed instead of scrapped by Norton after purchase.
There is an opportunity for improvement:
If Update Manager could be designed to cashe all update files first before actually making any system changes I believe that would save many hours of time in reloading and reconfiguring the whole system over again should the download process get stalled and the enevitable system lock up occurs which tends to cause great harm as you are forced to reboot in mid-update.