I currently use Shadow Defender, which is small and stable on my system, but unfortunately doesn't seem to be developed any more. Returnil looks like a possible new option, although I only interested in the freezing/snapshot features, and not interested in the anti-virus features. One big feature missing in SD is the ability to only use RAM as the cache, so no writes are made to the disk at all. SD also has right-click context menu item for committing changes (including optional deletions). I've read that Returnil has a memory cache - does this mean only RAM is used for the cache and no writes will be made to the disk at all (including the OS paging RAM memory to disk) ? Also, Returnil has the explorers for viewing and committing changes to the file system and registry. Does it also include a similar right-click context menu option, like SD, for commiting changes from explorer ? The multi-snapshot technology also looks interesting, so I'll be testing that out too. Does the first snapshot take a long time to create, with the following snapshots being quick as only the differences since the last snapshot are saved ? How does it keep track of the changes between reboots, and what happens if changes were made to the disk being monitored, while RMS is not running (eg. from another OS installation) ? If/when you do integrate MS into your other products, please also add it to the normal Returnil Pro edition, as well as the System Safe, since I would like to have this kind of snapshotting technology, but without all the cloud anti-virus technology.