IMO it's primary fault is it's low top speed followed by it's reluctance to climb from a slow start. That said it can turn like crazy with flaps out and I've often turn fought P-51's, 109K-4's and FW-190's without ever dropping my ord. I figure if I'm carrying ord on a mission I'm not dropping it until I absolutely have to so I got a lot of practice. Loaded it's still competative with those planes but they tend to extend and reset which they can do at will.
Jugs are generally outclassed by the F6F. Once the ord is gone the F6F is an excellent low speed turn fighter and like the F4F it's rugged as hell. That said in a high speed dive you have to be careful pulling out with ord attached or you'll lose your wings.
I wouldn't go so far as to say its
competative.... but it can hold its own given a fair chance. When I was playing, one of the things I least like to see was an ornery F6F pilot, because odds were good that if he was flying well, he knew the F6F well, and because they weren't afraid to HO anything without a spud-gun.
As for the F6F outclassing the jug, I would say thats true for the earlier models, but the D-40 can hold its own, and the M and N can walk away from you like the others. Also, I've never understood why everyone consides the F6F to be 'rugged' Yeah, if you're counting individual bullets its pretty tough, but I've never had one survive a tater, and they still die with a good burst from even .50's.