Was very pleased with how it functioned with Google Drive, though to be clear Google Drive files do NOT download unless you convert them to another format first or use some kind of separate conversion program (e.g. SyncDocs). I strongly dislike this "feature" but it's nothing to do with FTP Rush, this is Google's effort to remain "sticky" in organizations.
Homepage:FTP Rush is a free file transfer software for Windows, Mac, Linux, Android, and iOS. And it is not only an FTP/SFTP client but also a cloud storage client (support Google Drive, DropBox, OneDrive, and Amazon S3). With its tabbed Explorer-like interface, you can create multiple tabbed windows for different connections and easily download or upload files via Drag & Drop. It uses the local computer as a bridge to realize the file transfer function between servers of different protocols. That means files can be transferred between any protocols, such as transferring files from OneDrive to DropBox. It also supports the C# scripting language and provides a large number of practical interface functions and detailed documentation. You can use the scripting language to complete any custom tasks you want.
https://www.softpedia.com/get/PORTABLE- ... Rush.shtml
Status: Not portable, writes to C:\Users\USERNAME\Documents\FTPRush - tested v.3.4.0