To answer your original question, the ftp catalog is "usually" at the same state as the latest SUU. There are exceptions to this, but they should be rare. Using SUU as the repository is easier if you have problems connecting to the ftp site. At this time, the ftp catalog has later versions of the bios for 11th generation systems. An updated SUU (7.0) is scheduled to be released later this month and the catalog is going to be updated to match. if you would like,  you can burn the SUU iso to disc and feed that directly to the USC platform update function. You can also extract the iso files to a USB key (need 8GB key) and present that to the USC. An alternate method is to use repository manager (which uses the ftp catalog) to create an SUU disc or directory. This is a video of RM and you can see how it would work. The RM interface has changed a bit, but you can get the drift.  Rm installer: www.dell.com/.../DriverFileFormats
I have a brand new R310 and I wanted to run Platform Update before installing Windows OS. I have the iDrac Enterprise, so I guess I should be able to do this using FTP in USC, but the process stalls. When I attepmt to test the network connection, the 3 first tests succeed, but the final test, where it attempts to ping the ftp server fails. If I ignore this and just try to run the update anyway, I first get a message "Please Wait" for a few seconds, then "Connecting to FTP" for about 10 seconds, then "Downloading the Catalog" for hours and then eventually (the next day) it gives up. I am guessing it has to do with our proxy/firewall setup. (Curiously, I am not sure if I have to include the domain-name with the proxy username, like this: domain\user, and I can't try it out because the backslash character doesn't work in USC with a danish keyboard. Neither do any of the other characters usually accessible with the Alt-Gr key or Ctrl-alt key-combination - like '@' or '$' - very strange). I had kind of given up on getting FTP to work because I don't want to mess with the proxy server, so my plan was to just download SUU and get that onto a USB stick and let Platform Update work from there. But now I am a bit confused about whether I can expect the updates from the 4 downloaded SUU 6.5.3 isos to be as new as those Platform Update can pull directly off the FTP site. Can somebody shed light on this? Off course I would also be happy to get advice that can help me get FTP to work. I am leaving Address, User Name, Password and Catalog Location unchanged and I am filling out all the proxy-related settings: Server, Port, User Name and Password. I leave Type to HTTP. The proxy server is a Windows Small Business Server 2003 (so ISA 2004 I think) - soon to be retired. And there is also a hardware firewall outside of that. I am able to get on ftp.dell.com with Windows Explorer and download files from normal doamin-machines while logged on with a domain account, but not really when logged on with a non-domain account (I get some warning message and the Windows Explorer switches to Intenet Explorer, which presents a web-view of the FTP-site.)
Platform Update: FTP or SUU/USB