Yes, it is extremely difficult to sing a Queen song properly, not only because of the way most of them are written, but also the high standard performance associated with them. You can't beat Freddie...
In Hungary we have also had Queen day in Pop Idol...(or whatever you call it in your country). Here is the best performer from my country in case you are bored... ( she is quite good, actually, considering the facts I mentioned above and also that she does not actuallly speak English)