Depends on what you like. I’ve had both. In general A5 Japanese Wagyu is far more expensive and the meat is far more tender than Hanwoo beef. Eating A5 Wagyu is almost like eating the beef version of Foie Gras due to the way it melts in your mouth.
Hanwoo beef tends to be somewhat similar to American Wagyu in my experience – it has the chewy ‘beef’ flavor but with markedly more tenderness than the typical American steak – halfway between an Angus steak and a Japanese Wagyu steak – and the fat/marbling content is usually right in between these two as well.
I haven’t had the chance to directly compare these side by side though. There are a few Korean restaurants where they do serve Australian Wagyu and Hanwoo – and the Hanwoo is more than double the price (probably to take advantage of Korean nationalistic tendencies to eat their native domestic beef)
I mean this to me is absurd. Australian Wagyu sirloin at $19 and Hanwoo sirloin at $45.