The Me 109, in its several variants and long production run, was an excellent fighter, and the best fighter in the air until the arrival of the Spitfire.
The Spitfire was the first Allied plane in the war to equal the capability of the Me 109. An excellent short range fighter for both defense and offense. Indeed, the only drawback to the Spitfire in later variants was range. It was however rather fragile compared to U.S. fighters.
The Mitsubishi A6M was an great aerobatic dogfighter, and nothing more. It was fragile, and prone to fire, besides being rather slow. It was not necessarily superior to the F4F or the P-40, or even the P-39. However, used the way it was early in the war, it allowed the Japanese to have success due to the bad tactics used by the U.S. Simply put, so long as the U.S. pilots were so foolish as to try to dogfight the Zero, they lost. Once they learned not to knife fight with a slow aerobatic fighter when flying a faster, heavier, but better armed and armor plane, the days of the Zero were over.
The Focke Wulfe FW 190 was a true work horse, and a solid reliable plane with multi role capabilities. A real killer against both fighters and bombers. Possibly, maybe even probably the best German prop fighter of the war.
The P-38 Lightning was a success in both the Pacific and the MTO, and due to its design and the fact that the 8th never knew what to do with it, not a big success in the area of the 8th's operations. To saw it was not a success against the Luftwaffe is a false statement. It was successful in the 9th and 15th AFs. It was NOT a total failure with the 8th. It just wasn't a dramatic success. It still maintained a ration of 1.5 Luftwaffe aircraft destroyed in combat for every 1 P-38 lost for ANY reason. The only U.S. fighter in production form start to finish of hostilities, and shot down more Japanese planes than all others.
The P-47 was a real warhorse. Powerful, fast, heavily armed and armored. Later it had plenty of range once fitted with large external tanks. Rugged enough to be shot to pieces and still fly, it saved many of its pilots, even as a total write off. Easily the toughest ground attack fighter of the ETO, it was one of the best friends the foot soldier had. In Europe, only the P-38 had a heavier and more varied weapons load out or provided a more stable gun platform.
The Vought F4U Corsair. The only fighter tougher than the P-47. The only fighter capable of as heavy a weapons payload as the P-38. It held an 11:1 kill ratio over its enemies. Produced late into the fifties, it had the longest production run of any U.S. prop fighter.
The Grumman Cats, tough and relatively agile, easy to fly, and massively produced, the chief carrier fighters in the U.S. inventory. Fast, tough, and reliable, they were the backbone of the naval air wing.
The P-51 Mustang. A fast, cheap, and easy to produce, nearly disposable fighter. Too late in either Europe or the Pacific to be a war winner, but a capable fighter none the less. It was a relatively simple plane to fly, especially compared to the P-38, although it had no major advantage over a well flown P-38 or P-47 save speed. Had range and speed, and late in the war, mass numbers. It was easy to produce, and easy to maintain. It was 2/3 the price of a P-47 of F4U, and 1/2 the price of a Lightning. It was also incapable of carrying heavy loads of weapons, and it was a very fragile plane when used for ground attack. The cooling system was exceptionally vulnerable, and the engine extremely dependant on it.
The Me 262, the first and only truly successful jet fighter of W.W.II, and the most technologically advanced of the war. Had it not been for the short sightedness of the German leaders, it could have entered the war a year earlier. Had the 8th AF faced the Me262 with Eakers leadership, the disaster that was late 1943 would have been multiplied exponentially.