I really don't think the presence of a dog... real or otherwise... barking or otherwise is much of a deterrent. I really think only non-dog owners are attracted to the bark-alarm.
As a dog owner (pack leader) it is very easy to train a dog to react to YOUR reaction. Dogs.. as do people.. react to fight or flight in a natural environment.
Although it does happen... it is rare that a dog defends its owners stuff...
when the owner isn't there.
Generally intruders are most afraid of getting caught..
by another human. Having lights on timers is an old practice that still works. Using X10 and AHP you can create a set of security light-action timers very much like real life would produce.
Often burglars ring the doorbell to be sure no one is home... they can always ask for someone (that doesn't live there) if someone answers. I would think a light and loud radio in the basement or bathroom might be a better warning setup.
I am using an outright in your face
Voice Warning. That states the area is video monitored and an alarm is on. Mine is
automatically set but
can be set manually.