Run system check but press right until you see IOS 58 selected. Then post and let me know what it says. If sysCheck doesn't let you select IOS 58 then you don't have it.
Edit: after just looking at your post history and seeing your IOS 58 it looks like it's fine, so the issue is possibly the drive. Do you have the slow loading issue with more than just the 1 game you mentioned?