You'll see a lot of posts on new editions saying 'is it a steelbook?' 'oh no... it's not a steelbook!!' When it's in a metal case...
There is a company called 'steelbook' who make most of these special game cases and you can pretty much expect a certain quality / design style etc with their products that maybe you won't get with a 'metalpak' for example - newest rival manufacturer famous for their big spines on the cases!!
Check this out:
http://www.steelbook.com/
It's addictive mind....