It isnt that OEM isnt up to date. It is that it is tailored.
Like if it was a Dell OEM disc they are tailored to Dell PC's. Same thing with HP OEM discs.
So buying it from a New Egg site or something like that you dont know who the actual OEM (Original Equipment Maufactorer) is and therefor dont know which set of driver support it will have.
That is the only reason why people choose Retail over OEM. There is nothing wrong with OEM other than it doesnt have the full shot of driver support that Retail does.
I do not accept support questions via EMail, PM, IM or my G+ page!
Phone: LG Optimus G Pro
Running: Stock JB from LG with Nova Launcher