I've been playing with gFTP, it is really not bad. It seems to have all the basic features of the better windows FTPs, one feature I like about it is that it is multi threaded (like leech). Graphically it lacks a bit -- you can't increase or decrease the size of the GUI and it feels a little clunky. The one thing I do like about it is that it is fast. In fact I think it is the fastest ftp I ever used. It's written in C.
There is a new beta of gftp. It is claimed to be free of the file corruption problem of 2.0.7b. I've been trying it and haven't had a problem yet.
Interestingly, I didn't have any problems with an earlier version. I think it was 2.0.3 -- then I upgraded to 2.0.7b and started having problems. So far 2.0.8 is working fine. Which is nice because this ftp is packed with features and really is fast.
I've also been using Igloo-pro and it works and is stable - but it is slow and is missing a lot of features I'd like to have. There is also a 'artistic license' version floating around on the net -- I think it is called littleIgloo.
I tried some other graphic ftps, but they all seem to fall way short. Guiftp, and deadftp were half way there but they don't allow you to set file permissions.