Toughest doesn't mean necessarily best. Ok, put down that gun, I don't want troubles...
Ronchonner's style is awful and unrespectful, and I deeply disagree with many of his opinions, but some statements are true: training in Europe, altough excellent, is awfully and artificially expensive. Scarce opportunities to deal with busy airspaces.
Poor opportunities to build up hours(yes, maybe in UK you can instruct, but Uk is the exception: not all other JAA countries give the same opportunities...). The practical training is sometimes too diluted, due to weather in case of UK and other reasons such course organisation elsewere...
And not everybody gets an airline job with 180 or 240 hours. I'm digressing: the toughest licence, sure, and how can you tell it's the best too? Take a look at safety records for examples. Not too much difference between USA and Europe(at all). And according to this (arbitrary) criterium, the best licence should be the Australian one, since Qantas(maybe I'm wrong) is the only company that has never had any accident. Does it work this way so? How can you tell a JAA or UK pilot is better than a FAA one? We've got to warn Delta and A&A and United that they've hired and overpaid a bunch of assholes...Ah, when will they understand and train their pilots in Europe?
Put down the gun, again...