Section 2.5 starting on page 27 discusses "Autorotation" in detail, the procedures, probability, shortcomings, and training. It is an older document (circa 2001) but I would assume it is still valid as to describing the situation....and that suggested improvements in training, simulators, and NATOPs procedures have been made.
http://www.fas.org/man/dod-101/sys/ac/v22-report.pdf
I may be getting old and worry about my mortality more than I used to do...but even at spending 30% of my flight time in a phase of flight where the lack of a viable auto rotational capability might prove deadly....it would give one pause for thought.
If it isn't 1600 feet....what does the H/V diagram look like?