I'm with tc: the neck and eye strain is a on issue. Balance, correct adjustment, and just getting used to them avoids this. I have done 45 hrs of NVG in a month with no sore neck, and no eye strain. But. like anything, you do need to get used to them.
Congratulations on getting this up and running. NVG is the biggest advancement to night flying safety that I have seen in my career. Such safety enhancements should not be restricted to Police/EMS, as per the accident report into the Strathclyde EC135.
The Victorian Police are the vangaurd here in Oz and through some fantastic work, they should be up and running shortly. The entire Oz industry owes those guys a thanks.
I have two questions relating to the UK file:
1. What is the minmum standard of NVG that is acceptable?
2. Why have they not included "loss of visual reference on take off and landing" procedures as a requirement? I imagine that due to rain, the dust issue is probably a lot less likely in the UK than here in Oz, but what about snow or non compatible scene lighting causing flareout (this concern is related to the first question though).