PC: Windows Explorer for ftp
Of all the ftp clients I have ever used, including ones that I wrote myself, I have found that the best is actually Windows Explorer!
I have a remote server that I keep my websites on and to access it I open windows explorer in Win7 on my PC, I use the shortcut windows key + E to open it. and then I click in the address bar and type in my server name like this:
ftp.myservername.com
(but my real server name)
and it displays 'The Internet > ftp.myservername.com' in the address bar, and then I get a login popup where I type in my username and password and then I see a list of folders, just as if they were on my local machine.
Here's where it gets good, I can use those folders exactly as I use the ones on my local machine! (almost) which means I can copy and paste to or from them, windows takes care of all the ftp stuff and it is very good at it!
I did have a time where when I put an ftp address in windows explorer it would open my site in Internet Explorer, which didn't allow cut and paste etc. but I found a fix for it somewhere which involved running a registry script.
I can honestly say that this is all I use for ftp now and it really is the best ftp client that I've ever used.
If you have a windows PC and you try it, you won't look back