The Mustang might have been 'The Cadillac of the Skies'. Both had Merlin engines. The Mosquito was designed around the lightest aircraft possible with twin Merlin engines. To make it as light as possible, it had a wooden airframe, which explains why none are flying today. Because it was wooden, there are cases of anti aircraft shells passing right through it without exploding.
I have seen a Spitfire and a Mustang flying beside each other, and although they both had Merlin engines they sound distinctly different, because the exhaust stacks were differently shaped. The Mustang had an aircraft version of an automatic gearbox, another way of saying it had a constant speed propeller, the Spitfire did not.