Which is the "correct"/"official" kernel version? (server vs cloud-img installs)

I recently used official images to install bare metal servers and VMs (using a cloud image) and found out they install quite different kernels out of the box:

• 14.04.4 server iso (from here) installs "Wily" kernel 4.2
• 14.04.4 cloud-image (from here, "daily" build 20160512) installs original "Trusty" kernel 3.13

I understand that both are supported as of 14.04.4 (which is great!) and that I can upgrade them but this still begs a couple of questions:

1. Which should be installed by default?
2. Should it be different for the baremetal ISO vs the cloud image?

I ran into this because I'm trying to simulate a baremetal environment with VMs for testing purposes and assumed that images listed above would yield a reasonably similar environment...

(note: although this q relates to 14.04.4, I suppose the question might apply to future point releases, eg: 16.04.x later)