Likelihood to Recommend:Not LikelyExtremely Likely
Pros: I like that it's reliable and easy to use. It's the closest thing to being able to restore Salesforce as it was at a particular day and time. They also enable the user to copy data into sandboxes very easily. I researched different backup solutions and it came down to two -- OwnBackup and Spanning. OwnBackup is one of the oldest companies out there and its longevity and overall experience in backing up Salesforce orgs make it the wiser choice.
Cons: Every time you refresh a sandbox, you have to also update the new sandbox and sandbox metadata. This is a little annoying, but understandable because the URL of the sandbox naturally changes when you refresh it.
Overall: Peace of mind because if anything unusual happens to my Salesforce org, OwnBackup will send me an alert. I created a new sandbox to enable a delegated administrator to test some solutions and happily I got an email alert when it noted that suddenly 2500 records were added to my new sandbox. I had actually used OwnBackup to prepare my new sandbox with data for testing and even though in this case it was a safe change, it was good to know that OwnBackup was keeping me informed about potentially bad changes to my Salesforce org.