Users Group vs Devices Group use cases

As a rule i use Device Groups for any device related policies and broad sweeping applications like Office installations which i want on every PC. User Groups i use for all of the 'one off' policies. I do quite a few 'exceptions' as well when doing these deployments which gets a little more complex. Using the Dynamic Device groups you can hit 90+ % of what you need. Then tighten the last 10% with User Groups and Exception to the broad sweeping Device groups.