I would have to say that it was the Grumman F6F Hellcat. The Corsair had a VERY high landing speed, and had poor visibility. The F6F-3 was the first American carrier based fighter which had an advantage over the Zero. The Corsair flew 54,470 missions from land and only 9,581 from carriers. The Corsair may have done better against Japnese land-based fighter, may have been faster, and may have had a higher service ceiling, but I think that the F6F had a bigger impact on the from carriers.
Hey! Who you callin' ugly??? It was 10 times better than the Wildcat. Besides it's the inner beauty that counts right? How about that engine?