Back in the dark ages when i did all my dev work on a Windows machine, my FTP client of choice was FileZilla. It was one thing I missed in the Linux world. gFTP was ok, but sometimes flakey, and Konqueror did the job, but the layout was not as good as FileZilla.
So now the great news. Filezilla 3 is in beta not just for Windows, but also Linux. I am running 3.0.0-beta7, available in the Kubuntu Universe repository. So far smooth and reliable.