I would recommend getting an OEM version from somewhere like Newegg. The only difference is the licence gets tied to the first machine it is installed on and can't be transferred. But the price difference... $130!
Even cheaper again I would go for Windows 7 Professional instead of Ultimate. The only additional feature in Ultimate that average users would put to use is Bitlocker. The rest are all things like group policy enforcement, boot from VHD, extra terminal services features. Mainly things that only IT admins would ever use or care about.