Finals......I see there is the 139M....and the different Type 149....so two different versions.
The question raised by John Dixson is whether the US Army Design Spec's are met by the 149 is one that would bear answering as otherwise comparing the UH-60M to the 149 might be an Apples and Oranges comparison were that not the case.
The followup question would be which standard used....that by AW or the US Army is the superior set of critieria for a helicopter being built for use in combat.
Also....the final problem the RAF is going to have to confront is the lack of money considering the financial straits the UK Government thus the MoD finds itself confronting currently and for the foreseeable future.