WinRescue verifies the backup before it completes the backup. If there are problems with the backup, WinRescue will not complete the backup and you will get an error.
There is the Verify option in WinRescue which is actually a second verifying after the backup is complete but verifying the backup after it is complete is hard to do and does not always work. I only added this second verify because someone asked for it, but it is not needed. If this second verify fails, you will get an error. If you do not get an error, the second verify was successful.