I am quite aware of the Lightning's performance in Europe against the Luftwaffe, and quite certain that it was outclassed as a fighter. Quite apart from whather it was better than the Mosquito, it most certainly ws not better in air-air combat than a Focke Wulf Fw 190. Here's one statement I remember (can't remember where I read it though, annoyingly):
'During the North African campaign, the American P-38 Lightning had achieved a fearsome reputation as a powerful, fast twin-engined fighter that could severely punish the Axis pilot who treated it as his inferior whilst flying a single-engined type. However, once the later mark Focke Wulfs and '109s arrived on the scene - types that could outrun, out-climb and out-turn the Lightning, the nickname 'Fork-tailed Devil' began to seem a bit out of place. Whenever I encountered P-38s over France, the engagement, without exception, switched by default to a defensive action by the Lightnings, even if they started with a slight altitude advantage. Their first priority became survival, whereas we were the aggressors.'