Joe Schmidt's world No 2 side will begin a three-test tour of Australia in Brisbane on Saturday, some three months after beating England to clinch just their second Six Nations Grand Slam.
Ireland settled into camp by riding jet skis and visiting a theme park at their Gold Coast training base on Monday but Murray says they won't be in holiday mode for long.
"They're littered with talented players and it's always really demanding on your lungs," the British and Irish Lions star said of the challenge the Wallabies present.
"It's often played at a quick pace and this group wants to test themselves against the best.
"We've all been aiming for that for quite a while and now want to put down a marker against one of the big dog teams."
The 29-year-old is respectful of his opposite number Will Genia and aware his men will be peppered by high balls thanks to the presence of aerial ace Israel Folau.
"He can jump quite high, can't he?" Murray smirked.
"Sometimes it's hard when he gets a good leap, but you've got to compete and try to stop it."
Ireland have found ways to stop everything thrown their way so far, also boasting wins against New Zealand and South Africa under Schmidt's reign.
But, pointing to Australia's defeat of the All Blacks in their last Brisbane test, Murray says the Irish can't expect to waltz to another victory on Saturday.
"They are class, they express themselves, play with width and have dangerous athletes out wide," he said.
"Everyone's buzzing to be here ... we were in a good spot at the end of March (after clinching the Grand Slam) and need to step forward again."
The possible reunion of backrow pair Michael Hooper and David Pocock is also on the mind of Murray, but he knows his duel with Genia will be a talking point regardless of the outcome.
"No 9s and 10s, when things go well you get praise and when they don't you get slated," he said.
"Will's top class and his form is right up there at the moment ... it's a challenge people are looking forward to."