I had a bit of an adventure driving in Australia earlier this month.
I spent a week in Australia at the beginning of October, including 2 days in Perth where I rented a Car. I could have used public transportation and Uber, but I'd never driven in a wrong-side-of-the-road country before and wanted to try it. Phdhorn hit the nail on the head in post #7. It's not hard, but it takes more of your focus. I was able to drive through the morning commute to the Central Business District (i.e. downtown) in a city twice the size of Austin without any problem, but I was completely focused on driving and Google Maps.
On my last night there, I was heading back to my hotel near the beach/coast after an exhausting day and decided to get a fast food snack a few files from the hotel. At about 1AM, I pull away from the drive thru with my food and start to make a right-turn in to the near lane. With virtually no traffic to remind me of the flow, and clearly not enough focus, auto-pilot took over. I probably only got half way through the turn onto the road before I realized my mistake and backed up...then turned right into the far lane. No blood, no foul, right? Ah, no. About a minute down the road I got lit up by cop lights. Fuck. I've been pulled over for tickets before in the US, but I know what US laws are, and I know what cops can and can not do. It never occurred to me to research that for Australia.
They were pretty chill, but they told me that based on my driving I was going to need to go with them to the station for a breathalyzer. I wasn't sure if it was a request I could refuse, or an order that I had to comply with. I've since looked it up, and it was an order that there was no option of saying no.
A ride in a Police Van, a breathalyzer, and an hour of my time later it was all sorted and I was back at my hotel, and as an added bonus, they didn't give me a ticket for initial turn into the wrong lane.