basic gentoo question

[Jude DaShiell]

Those iso's on the gentoo.org site have contents and digests files tat 
accompany them.  To attempt a proper iso image download would the gpg -v 
livecdxxx.iso command be all that's needed provided the contents and 
digests are also in the same directory? I know for sure I've downloaded 
bad gentoo images given media errors that always happen when trying an 
installation, I just want to be certain what I do to verify images before 
installation is the right procedure.