Aussies... or not?

Here you are! Three new versions of one song. As usual, listen and tell me what's your favourite one and your opinion about them.
Ops! One question: what's the link between this song and Scotland? Discover it and tell me in class.

Cover 1 :Yihaaaaa! Some great Bluegrass stuff.

Cover 2: Are cellos only for classical music? Not so sure, hmmm...

Cover? 3: The real deal. Hats off, ladies and gentlemen.