What are some alternatives?
When comparing Cloudu and FileZilla, you can also consider the following products
Filestash - Filestash is a modern client for FTP, SFTP, S3, WebDAV, Minio,...
Cyberduck - A libre FTP, SFTP, WebDAV, S3, Backblaze B2, Azure & OpenStack Swift browser.
FlowCloud - FlowCloud is online cloud storage GET 120GB FREE!
Beyond Compare - Beyond Compare allows you to compare files and folders.
Dropbox - Online Sync and File Sharing
PuTTY - Popular free terminal application. Mostly used as an SSH client.