Blackbam

Create, manage and view snapshots of any post (or custom post type) whenever you want. Like user-managed revisions with a lot of useful functionality.
Features: 
* Create snapshots of any post type including all metadata at any point manually as a secure history and backup of your posts 
* Uses the standard WordPress posts table (like revisions) 
* Uses a custom post status (and therefore works for any post type) 
* Easy snapshot management meta box 
* Create Snapshots comfortably in the publish post box 
* Choose which post types you want to enable the snapshots feature for
PHP Developer API: 
 pos_create_snapshot_from($post_id): Creates a new snapshot for a given post ID 
 pos_delete_snapshot($snap_id): Delete a snapshot by its ID 
 pos_get_latest_snapshot($post_id): Returns the ID of the latest snapshot for a given post ID 
 pos_get_plainview_url($snap_id): Get the URL to the plain snapshot view
This Plugin is sponsored by ready2order GmbH, the company which is producing Austria’s best point-of-sale system. Visit us at https://www.ready2order.com/.
NOTE: The use of a custom post status in WordPress is still in beta. The developers of this plugin are in no possible case responsible for any data loss. 
If you want to be sure nothing happens, backup your database on a regular basis. You should do it anyway.

Post Snapshots

Everything works as expected and I did not hear any compaints yet.

On our live website it has been working great since two months now

Create, manage and view snapshots of any post (or custom post type) whenever you want. Like user-managed revisions with a lot of useful functionality.

Mindvalley

Have a crap ton of sidebars and widgets setup?
Losing sleep because you’re afraid to lose all those settings if someone messed with it?
Look no further. Use this widget to
<ol>
<li>Take snapshots of your current widget settings.</li>
<li>Restore previous snapshots.</li>
<li>Import / Export snapshots as XML.</li>
</ol>

MindValley Widget Snapshot

Takes snapshots , enable import and export widget settings & configurations.

Post Snapshots vs MindValley Widget Snapshot