I'd say the Jug does require discipline to get the most out of it. There's a lot it can't do as a dogfighter as well as most of the planeset but it does a few things very, very well so the rules to flying it well are easy to govern in a dynamic environment.
In the typical little MA skirmishes and 1v1s below 10-15k, I think the ki84 gets the edge. By 15k the D40 holds the edge. The thing I really like about the American planes is the WEZ (weapon engagement zone) bestowed by the .50 cals. In a many vs. many, most planes have to "latch" to get a kill including the Ki84,K4 and Spits. "Latching" requires time, sucks away a ton of SA and makes your maneuvers predictable as long as you're prosecuting your target. Not only is the Jug tougher, but Jugs rarely "latch" because it's not something they're successful with. Rarely would I shoot at anything beyond 400 in the -84, there's not a lot of deflection available because of the inferior ballistics and not enough bullets available (only ~10sec cannon) to waste. In the Jug (20-30sec firing time) I can consistently take "hoser" shots out to 800 with more deflection and more confidence in a kill.
