probably a bit big for solid winds at your weight. can you check what other guys in the area are using regularly in teh conditions you will go out in?
9m for a beginner your size in WA is pretty standard for a first kite / no quiver yet, to be able to get out in an ok wind range - but maybe the 11.5 suits your conditions?

i've read that the kite itself is pretty good over the years - but no personal experience with them.
all the best with learning!

As a beginner this kite will suit you well. Add a 9m to that and you will be kiting in all winds
The Argo kites are very user friendly and most defiantly have the best relaunch abilities, gets you out of s#*t in the surf
The Argo is also great for intermediate to advanced, so you will enjoy this kite till the end