WinSCP has been a go-to tool for Windows sysadmins since 2000. If you've ever SSH'd into a Linux server from a Windows machine and needed to move files around, there's a good chance WinSCP was involved. It's free, open-source, and deeply focused on secure file transfer — SFTP, SCP, FTP, and more recently S3 and WebDAV.
FTPie is a different kind of tool. It supports the same core protocols but wraps them in a broader package — cloud storage, built-in file viewers, backup scheduling, and a bunch of extras that go well beyond file transfer. It's also Windows-only, but that's where the similarities end.
The real question isn't which one is "better" — it's which one matches how you work.