The so called conspicuity colours and whether they are effective is open to considerable conjecture. Ask people at Shawbury where several 350's & 412's have these paint jobs. One person even mentioned that he found it difficult to see when it was hover taxying past in front of a dark backdrop. What hope when you are low level! A combination of HISL's/Rotating Beacon/TCAS/MRB colours must be the best option.
It surprises me that some police air support units slavishly adopt this paint scheme but hesitate about spending more cash on a TCAS or a couple of HISL's. What is even more surprising is that one purely 'congested area' unit has this. Lots of low flying jets eh??