Well, those guys pretty much sum it up.
I use flaps pretty freely, but absolutely try to put them back up as soon as possible, and avoid getting myself in a position where I can't get some speed back. I really prefer to operate in the 175-275 range. I use them freely, but briefly.
The F4U will stay stable slow with full flaps, but gets to a point where you're far from effective. At that point I consider that I've really screwed up, and I'm left hoping the other guy screws up worse. For me the warning bells start going off any time I need to leave 3 (or more) notches down. I may not be dead or in big trouble at that point, but I will be soon if I don't make some quick adjustments.
I may go so far as to quickly drop 4-5 notches, but that genmerally leaves me in a do-or-die situation. For me to do that I'd better have a quick shot opportunity, and I'd better hit it.
My main use of flaps is to aid in nose-high reversals. I'll pull up at an angle, and drop a notch or two as I pull through the turn. As soon as I'm nose-low again I'll start bringing them back up. I may do that 20 times in a fight. My other big flap-usage time is in some version of a rolling scissors. I'll fly in lag pursuit, and drop flaps as needed to solidify that my opponent is pulling out in front, and then try to raise them so I have enough speed to catch/kill him as he pulls up, or stay with him if he dives out.
A big "hint" for me is the wing-wobble stall. Any time I get that I think "Oops, shoulda dropped another notch right before that happened". The other big hint is when they blow back up. I'm thinking "Oops, shoulda raised 'em... Killing my E by having flaps down as I accelerate..." Flaps for me are about a brief stability gain, or a brief aid in turning. Not about being able to fly slow. If I'm getting to the point where I'm getting slow and need another notch to stay stable, and then another, and then another- I'm in really big trouble.
If I'm getting to the point of being in the 200mph range, without the ability to finish the fight immediately, I'll generally break off at an opportune time (me nose-down, him nose-up, even if I'm low) dive and level to get back to around 225-250, and then turn back into him, or turn so he approaches me from the side so I can manipulate that into an overshoot. I really feel hamstrung if I'm loitering around the 140 mark. I need 130 to really do what I want to do, and 140 is close to dead for me.
My mentality in a fight is to try to get the other guy in front of me, rather than to try to get behind him. That's a pretty vague distinction, but it's how my mind works. To that end, the more he fears that I'll run away the better. So I'll present my tail in an effort to get him to go as fast as possible, and then give him my side-view, so he'll close rapidly while I can still maintain my speed. It's a way for me to get the overshoot but not be slow, so I can stay with him as he goes by. My mentality is that I want him fast enough to go past me, but I want to be fast enough to keep up when he does. I DO NOT want to slow down so he'll overshoot, I want him to speed up...
I'm also generally going to avoid being directly under anyone. I always try to maximize horizontal seperation, and minimize vertical. When the bad guy dives in I'll turn back under him, hoping to maximize his speed in the dive and screw up his shot.
Pretty vague I guess, hope it helps anyway. Give me a holler sometime, we can go play in the TA.