[CentOS-devel] Checking signed repo metadata by default?

Hi there,

I stumbled upon an older post by Johnny Hughes about gpg-checking the 
repository metadata. [1]  In the mean time, we seem to have signed 
metadata not only for "updates", but also for "base", "extras" and 
"centosplus" (just the "base" signature for CentOS Linux 6 is missing).

What are the reasons for not enabling the repo gpg check in our default 
installation?  Would it be a bad idea to do that in our Vagrant images?

Best regards,
Laurențiu

[1] 
https://seven.centos.org/2015/05/signed-repository-metadata-is-now-available-for-centos-6-and-7-for-the-updates-repo/