Insync is a powerful, feature-rich backup and sync application that makes backing up and syncing data between different computers, hard drives, and cloud storage accounts a breeze. With Insync, you can easily sync files and folders between computers, external hard drives, and even cloud storage accounts. It supports a wide range of popular cloud storage services, including Dropbox, Google Drive, Microsoft OneDrive, Box, and more. With Insync, you can also backup files to a local folder or external drive, or to an FTP or SFTP server. Insync also allows you to quickly compare folders and files between computers and cloud accounts, as well as easily upload and download files from the cloud. Insync also includes several powerful tools for managing multiple accounts and devices, including the ability to sync files between multiple cloud storage services, and the ability to set up multiple profiles for different users and computers. In addition, Insync includes a powerful backup system that can be used to back up data to a local or external drive, or to an FTP or SFTP server. Additionally, Insync includes a wide range of features for securely sharing and collaborating on files, as well as advanced security and privacy features.
It's free, but it's not really an accurate alternative. It mounts Google Drive as a network drive and, in my experience, there is a delay in accessing and saving files.