Theater actors are the best to work with in my opinion.  They know what it is like to memories lines for an entire couple hours or so.  They know how to hit their mark and say their lines on Q. 

Most actors are fluent in improve so if a scenario arises that is random or unplanned they can quickly adapt and move forward with the premise.  These little miracles make it a blessing to have when moving quickly on a small few million dollar movie. Time is of the essence. 

All egos aside ( and of course this is the hub for egos lets face it ) theater actors are valuable and should be treated as so.  The day of not paying actors is history. All actors should get paid.  No matter if its a small student film or a big Hollywood production. 

You get what you pay for in this biz.  If you want a smooth on time production hire professionals. If you don't care and just starting out and learning hire beginners.

The safe bet is hiring theater actors.  Can't go wrong.