The Chinook and the Apache are the mainstays of the Afg op.
There is a niche role for either the Sea King or Merlin, but to deploy both is a purely political move. One or the other would be welcome.
I think you'll find that CHF and all the crews don't think it's niche role. Nor do the 47 crews the SK take the strain off on the smaller tasks. We have been out there for nearly a year now y'know