Buy the OEM its cheaper and will work, all you really need is the product key anyway.
THe best thing you can do for a new build with Windows 10 is use someone elses computer to download the Windows Media Creation tool and make yourself a USB installer, you can use any 1GB+ USB drive to do it, and in creating it, it downloads all the latest updates so when you install you don't need to sit and wait for it to update a bunch of times when you first start using it.