The 902 is certified and legal SPIFR in the US and JAA countries (any delays in the UK are probably courtesy of the CAA). In its IFR version it is as well, if not better equipped than most of the IFR aircraft operating on the North Sea. I believe that Sussex Air Support Unit are happy with their aircraft which has a full Police and Hems fit,(although it has to be said that they do not operate IFR).
The lack of information about any potential snags with the 902 may be because there are few that cause any of the operators any real concern. The current rotor and wing magazine contains an unbiased report of the 902 which should convince you that it is a capable machine for HEMS work.
Personally speaking, I can't believe that I'm lucky enough to have flown in one!