... remember 139 and 189 don't have ...
What?
... I keep hearing negative reports about many aspects of the new service which I do balance against the fact that they are still rescuing people.
That balance Crab: do hold that thought.
I could give you negative reports from CivSAR recently and going back a quarter of a century if I thought that there was any point when I know that people have taken things on-board and set on improvement and, as you say, balance against the fact that they are still rescuing people.
Likewise in the MilSAR, how many broken aircraft, bad comms, new boys making wise but restrictive decisions about their own capabilities, and my all-time favourite, telling us they had to leave the exercise early for an appointment elsewhere and then being spotted having lunch in a nice hotel (a bit obvious with something yellow occupying a large part of the car park visible from miles away).
Key to what is happening just now is new boys making wise but operationally restrictive decisions about their own capabilities. The knowledge pool for the Westland Sea King under military flying rules is immense but the knowledge pool for S-92A under CAP 999 and various OSR and so on is still small. Likewise, the knowledge pool for AW189 under the same regime is as yet non-existent and by Q3 2016 will still be mainly maritime.