The Gnome is/was a good engine....when it worked properly...economical,light,good power....but it needs setting up properly with the computer...
It did not take kindly to operating in tropical conditions,where everything gets wet/damp,dusty/sandy,etc.,and being in the nose of the Whirlwind,with only a gauze screen intake,poor protective treatment of the 10-stage compressor blades and IGVs,one would get power losses after 25-50 hrs,and no torquemeter .The computer electrics likewise were a problem,so one could end up doing a sortie in `manual` throttle.Similarly,the `engine surge margin` became degraded,so it could lead to a surge,,HP COCK OFF,lever down ,forced landing.....Had 2 of those...A helo engine ,in my view,should have at least a couple of centrifugal stages at the front ,as they are more resistant to wear,and give better surge protection. Best engines for rapid response..Astazou in Gazelle,and Nimbus in Scout/Wasp....you can pull from joined needles to max in less than 1 second..they may surge(very audible),but no flames out of the jetpipe...Yes you can do that in WX and SK,but the HP cocks are electric(2 seconds) and if it surges,there`ll be metal in the jetpipe......
Globo...Wessex 1 and 3 Napier Gazelle,different Mks,and Belvedere.....another good engine...maybe the Navy might not agree....but a lot depends on the operating environment.....

thats my 50 p worth....

In nearly 6000 hours of flying with the Gnomes in Wessex and Sea King, I had one partial rundown and one real computer freeze so I'm pretty happy with their reliability.

I flew with the FAU (Uruguayan Air Force) a few years ago and they had a dispersal full of old Wessex we had sold them many years before. They had had such problems with them because they didn't know how to set up the fuel computers that they became impossible to use (no manual override on a Wessex).

I enjoyed the challenge of wet winching in manual throttle in the Whirlwind 10......but not a lot.

Those winchman deserved a medal.

Those particular Wessex (ex 28 Sqn if I’m thinking of the same five airframes) suffered very poor serviceability in the latter days of their RAF service; it’s hardly surprising that engineers with far less experience had trouble with them.

Whirlwind computer control was, obviously a great advantage. At Valley, we had a Master Pilot returning to S&R after previous tours on the piston WW and his hovering was 'variable' ... until he went 'computer out'. Instant perfection and rock-solid rotor speed! How long does 'muscle-memory' last?

CJ, in the late 1970s the French exchange QHI at RAF Shawbury had apparently never flown an aircraft with a computer controlled engine before he began teaching on the Whirlwind 10. His students hardly ever got to fly computer in, he obviously thought it was too easy (or maybe out of his personal comfort zone).