That's exactly the kind of information I was hoping to hear to the question in my first post. Using the AED is just the beginning, not the end, of a crisis. But, if you're going to go so far as to routinely set up a landing site for a medevac helicopter at your work sites, as you said, it could still tip the scales towards the AED if the response time is not too long.

Also, the kinds of cardiac situations you'd typically face on your job site may not reflect what an urban medic sees, so Polak's experience may not be 100% transferable to your situation in terms of how much post-AED care would typically be required.