bayfiles: some people said they have a lot of "file not found" issue

putlocker: it's usually hard to upload. FTP has low speed, and HTTP upload usually hangs forever (you have 30 ~ 40% chance to get higher than 30MB/s connection so you have to monitor it, disconnecting slow ones and restarting them again and again)

zippyshare: mass delete files according to an uploader's IP, and stop accepting any uploads from that IP (you will always get 404 not found after each upload job has completed)