To me the most overrated plane. far and away, is the Me 262.
Sure it was the first jet into regular squadron operations, but the effect it had was nothing comarped with the resources expended to develop and deploy it.
The B-17 bomber stream was the SAME whether or not the Me 262 was there, and Me 109s produced in lieu of the 262s would have done more damage to the bombers, if only because so many more Me 109s could have been built using the resources dedicated to Me 262 development and deployment.
I think this is a personal opinion. The P-51's real performance is as good as the hype. I never heard it built up to the point where it was claimed to be better than it was.
When it first escorted B-17s to Germany, no other plane could have done that or they WOULD HAVE DONE SO. It was faster than most operational Spitfires, but I've never yet heard anyone claim it could out-turn or out-climb a Spitfire.
All of the comparative tests I have read were done by the British and they weren't too keen on touting the Mustang, so almost all the Mustang performance data was taken at normal power (no WEP) using 87-Octane gasoline, and limiting the boost to something like 12 - 18 inches ... while the Spitfires were allowed to use WEP, 100 - 150 Octane gas, and were allowed to use 25 inches of boost or more.
In these circumstances the Spitfires almost always came out on top, as the Mustang would have done had the restrictions been reversed. Restriction tend to muddy the waters. In point of fact, the Mustang was a good all-round performer and was probably not the BEST in any single category.
The Spitfire was a specialist with no apologies for being such, and was always kept as light as possible for the fighter-interceptor role. T
The Mustang was loaded down with fuel and whatever else was deemed necessary for the escort role.
Perhaps you people who feel the Mustang was overrated could post the exaggerated claims you have heard about the Mustang? I would be curious to read overinflated claims about it. I'm not saying you wrong (actually, I'm a Spitfire nut myself), I just want to read about the overinflated claims of the Mustang's performance.
Cheers!