I have always felt that the P51 in AH did not measure up to the historical record as I understand it, but I am no expert and have never flown any genuine P51s to compare with, so I just accept the way the plane behaves in the game and try to work with that. It is interesting to note that there are a few guys who ride in the 51s in game who do a remarkable job dogfighting close in. Almost always astonished when I come across one that flys sharp angles at high speed and appear not to lose much (if any) energy. That aint me. I employ very wide angles and try to use the plane as a backstabber (or picker....if that suits you). When it comes to turning with most other combat rides in AH I quickly lose angles and end up diving out or getting waxed......so I stick with the high speed retention use of wide angles regime. Seems to serve me the best in 51s.
You have to understand that the way the 51 is used in AH isn't anywhere near the way it was used for real. None of us take off in a 51 with full internal fuel, two 110 gallon DTs and fly a long range mission at high alt escorting bombers. Remember the altitude the combat was taking place at. Remember the conditions. Because we don't really risk anything, we don't fly the same way
Go back to the DGS scenario and the way the 51s were operated along with the other Allied rides the 47 and 38. It was high alt, long distance flying and choosing combat when it made sense, but knowing you only had one life. Protect the bombers, kill the fighters. How we flew in those situations was nothing like we fly in the MA. The 51s operating in pairs did well but they flew it like their life depended on it. This applied to the 38 and Jug guys too.
The 51 is a very survivable bird flown to it's strengths and had I not been in a 38 I'd have wanted a 51 as it was the best for the job.