Worth watching, stick with it. Gritty show from Australia which I found quite believable, unlike shows in the vein of Ray Donovan etc. Having known a few people in my time on earth that actually made a living from crime and violence, I found the portrayals realistic. There is no glamorized violence, kung fu, CGI BS or 90 pound women in high heels and evening dress beating up 220 pound thugs, so if that fake Hollywood world is your thing, this is not for you. In the real world, people are multi-faceted, and this show does a good job of presenting that with the main character.
I am not Australian, but I didn't need subtitles to understand the dialogue.
As for the reviewer who said the main character is a rip off of Mike from Breaking Bad, you are wrong. The lead in Mr Inbetween is a direct recreation of the lead role in The Magician, 2005, an Australian movie. Scott Ryan wrote the movie and played the lead, and he is a writer on Mr Inbetween and also plays the same character. Note Breaking Bad didn't air until 2008, 3 years after The Magician, so if anything, Mike is a rip off of Ray Shoesmith.
Don't miss this show if you like realistic action, settings and characters. If you like Hollywood and typical UK PC police procedurals, you might not like this. Personally, I found Mr Inbetween a breath of fresh air.