Spoke to the lads in the Spray Shop and asked them about the Hi-Viz stripe. They said because of the nature of the paint it didn't weather well at the "higher" airspeeds of the aircraft, which caused wear and tear and made the paint fade. As this paint is expensive, and had to be re-sprayed on a regular basis, the dept of Justice/Gardai reckoned that as the Defender is being flown and maintained by the Air Corps, it was up to them to keep up the scheme. So the Air Corps dropped it. It is different for the Garda Heli's which are maintained by Macalpine.