Yeah I think British FAA development is very often wrongly mocked. With people comparing aircraft to types introduced years later, ignoring the realities the RN was operating under and its initial limitations placed upon it thanks to the fact that the RAF actually controlled the FAA for a long time. That being said while the Fulmar is impressive in terms of what it managed the thing was still built under a misguided concept and compromised in performing its role.
Just a slight correction. That should be 450 km/h or 242 knots or 280 mph. My chief complaint about Western aircraft carrier borne fighters was that the aviation engineers, as well as the air services, did not take account of what was needed to make a competitive naval fighter if and when land-based fighters and bombers were to be fought.
In the case of the Fulmar, the Merlin-60 at 940 kWatts or 1,290 HP was better than a Pratt R-1830 at output though 200 kg heavier. That required the RR to be front-nosed onto a Fulmar that was about 750 kgs lighter than it was and about half the guns and was shy 1 crew member.
What the British called long-ranged was a joke to both the USN and the IJN.
Sadly the Fairey Firefly, the Fulmar's successor, with a powerful 1,700 kW RR Griffon engine, which should have been contemporary with the Hellcat, showed the same climb, turn and service ceiling limitations relative to the Hellcat as the Fulmar did to the Wildcat. In the British plane's favor, it could carry a formidable bombload. About 2,000 lbs of bombs on the wings.
BTW, did you know the Hellcat could drop a Mark 13 torpedo or 4000 lbs of bombs? That is ridiculous. It is almost a strike fighter.