First if you live in these countries and can watch these shows, your lucky.
I watched the last amatuer version of MasterChef England via a proxy server and I am watching some of MasterChef Australia via download.
I don't know why the BBC and Austrailia TV blocks international viewers for shows that are never going to air overseas.
They are so much more about cooking and less about drama than the American counter parts; Top Chef and Chopped. (Don't get me wrong I watch those shows too)
If you get a chance and can muster up the amount of work required to find episodes (cough... torrent... cough)
I recommend both