As said above, the 20mm rounds are good at long range because there explosive and blow up on impact, there not just slugs like the .50 cals. The 30mm's weren't build for range, just pure power because there explosive too, but there also low velocity, so there range was very limited by that and it's very short barrel.
As for the P-51's, yeah, from what I've read and talked to P-51 pilots (I used to work for the Yankee Airforce before it burned down and there was a P-51 owner on Willow Run with us) that the P-51 has low speed handling problems, but once above 200-250 they were gone, and turn rate was outstanding, the wings were built for life at higher speeds, thats also part of the reason it had such good range, less drag and a high speed (and large fuel tanks)= REALLY long range.
And my last part is actully a question, if the aileron is smaller on the later models of Spits, why does the spit Mk1's roll rate slower then the later models? Damn thing turns like a Zero but rolls like Typhoon! lol
Edward
