Self signed SSL certificate usage [duplicate]

My scenario is about a closed system utilising a db driven website. It’s not supposed to be open to the public and the URL is hidden.

Currently I use Commodo certs to do the SSL, but I’m wondering since it a closed system whether it makes sense to use a self signed one. Is there any danger to this? I control all the end users computers so could easily install the cert in their browsers.

This is very different from the question marked as a dupe, it’s not a LAN environment.