I don't like getting the F4U under 250mph TAS if I can avoid it. She may have one of the best turn radii in the game, (this isn't the place to debate how things are modelled) but the turn RATE suffers so she'll ultimately lose a prolonged turning contest against most opponents--you HAVE to take the scalp QUICK or he's going to be around on you. It takes an experienced stick to know where to put his nose to get that shot in a low-speed fight, and moreover takes someone who's a good shot to be able to take advantage of that opportunity when it arises. As has been pointed out, the F4U requires a lot more hands-on work to really take advantage of what she can do in a fight. The flaps are superb, but it takes experience to know when to deploy them. Too soon and you'll overshoot the turn. Too late and you won't get around enough. Also, changing directions while hovering at the stall is very dicey. Stability may be a little better in the stall than it should be (but this can be said to varying degrees for ALL planes as well) but as much time as I've had in her I still let her get away from me, especially when changing from a left to right turn.
Additionally, unless you're in a -4 (and considering the circumstances of the post it's a pretty good bet he's not) once you shed all that speed to turn with the Spitties you're in BIG trouble. More than most other aircraft in any multi-plane engagement the F4U needs to stay fast.
There's a rare few pilots that can hover around at 75mph and rack up 5+ kills in a 30-plane furball and get out of it alive to land them, but I don't recommend it for most players, especially those just learning her. Keep her between 250-350mph though and she's one of the best all-around fighters there is (build up the perks to take the -4 for a ride and you'll find out why she IS the best). She just takes time and practice to really become rewarding.
But if you're looking for motivation, just remember...
