The P-47 for me. It was outstanding in all phases of air combat, from aerial engagements to ground attack. It also had good range (later models had outstanding range, escorting B-29s to Japan and back). Above all, it was beloved by pilots for its ruggedness. The USAF should have retained the P-47 for use in Korea instead of the P-51 due to its firepower and survivability in the ground attack role.
I may be alone here, but I think the P-47 is a beautiful airplane, especially with the bubble canopy. Pilots loved its roomy cockpit and mild-mannered flying characteristics. The wide undercarriage made it easier to land as well.