I'm building a new mid-high spec PC and it's main use will be for gaming. I'm concerned about it having Windows 8, as it forces me into getting it as my OS and I've never used it before. Will it run any games I plan to play without any issues? Games played will include MMOs such as Final Fantasy Realm Reborn, League of Legends, and shooters such as Bioshock Infinite and Fallout. I'm not sure why I'm not given the option to choose my OS, as I would rather choose Windows 7, but I also don't want to shell out $200 for a 'downgrade'.