Download the audio tapes for "in their own words." One of the vets interviewed was a loggy who cleaned and repaired tanks to send back into action. Sobering.
Early after D-Day most of the first generation M4's were having real troubles with survivor rates. Soon though, all of the M4s with wet-storage ammo bins and the larger 76mm gun began to be used in more realistic tactics. In tank school these men had been told they had the best tank, which was true but it is not designed for tank-vs-tank combat. There were many 76-mm M4s that crews survived as many as five tanks being knocked out. And of course, with proper tactics they did manage to knock out even Panther tanks. Even then it was not within their design to fight tank-vs-tank.
Aces High is nothing like WWII when it comes to the tactics, of course. While we have the tanks, we do not have towed artillery, Division level combat, or infantry. Finally, the restrictions of terrain that kept the Panther on low and level ground does not exist in Aces High. Even the M4 can traverse much steeper ground in AH than it could in actual fact. That's a game concession that we must live with since the terrain itself is not intended to be realistic.