Student download of Windows 7

Hey guys i'm looking to download win7 64-bit from digital river and it's saying i "need" to order the backup dvd since i have 32-bit vista currently. I googled it and only found this: link. It's my exact question but they didn't say if it's required or not. I'd rather not buy if i don't have to. so can i download the 64-bit .iso and do a custom (fresh) install or do i have to buy the backup dvd?

oh come on guys.. no insight at all?

There shouldnt be a reason why you would "need" a backup disk. The only reason I can see them wanting you to do this is if the download was corrupted and the install failed leaving you without an OS. Either way you should be able to make your own backup disks through vista.

yeah that's kinda what i'm gathering from it too