First of all the major difference between Windows Premium and Professional for the home user is that Professional allows seamless use of programs designed for XP platforms so your older programs are not redundant.
Having just built my first computer I decided if I was going to take that plunge I should go for it completely and get a "builders" copy of Windows Professional and I was not disappointed. My intention was to set up and keep the computer for some considerable time anyway. So although an OEM copy isn't transferable as it "ties" to the motherboard that was never a worry for me. Given the saving against a retail version and the competitive price on Amazon it was not a difficult decision! So if you want an operating system with all the features of a retail version but at two thirds the cost and don't have any reservations about restricting it to one computer ... go for this copy!