My phone came pre installed with portico update xxxx.xxxx.1308.xxxx but still didn't have the fancy storage check option in settings so I googled it and found the way to get it. I found that those who had it, some had same firmware as mine while some had older than mine. But their Extras+info was newer than mine. So here is the way. And also please thank me for it.
As well as the nokia discussions from where I found it.
You just have to update the following apps from Windows phone store by manually downloading and installing through sd card (nokia).
Feedback To Nokia: http://www.windowsphone.com/en-gb/st...2-50bd030730ec
Access Point: http://www.windowsphone.com/en-us/st...3-25c10463942d
Network+ (previously Calls + SMS): http://www.windowsphone.com/en-us/st...c-2afd1c95c245
Extras + Info: http://www.windowsphone.com/en-us/st...3-fc517345a3c0
Display + Touch: http://www.windowsphone.com/en-us/st...8-f92e9c7994f3
After updating these apps you are sure to see the "Storage check" option in settings
Do not forget the most important is Extras + Info because this storage option comes inside this update.
Now hit thanks if I helped you. And mods please make it sticky.