I went through the exact same thing.....AXIS....ARX....AXIS.....ARX.....I was bidding on both but what I got was a great deal so I ended up with the AR-X....and a lot of change in my pocket to get the car to how I wanted it.
In the answer to sporty or a bus on cross-pliers(american shitbox).....The AXIS is the more sportier model being 100kg's lighter and is already set up pretty good.....but that is nothing a good set of springs, shocks and swaybays cannot fix on the ARX. Remember at the end of the day this is a station wagon so if you think you are going to end up with some sort of R34 GTR you are mistaken.....in saying that I don't think you will ever see a Ford Territory, Falcon Station wagon or a Adventura/Commodore keeping up to one of these in the wet......and they will be battling in the dry as well.
In answer to the standard suspension on the AR-X....it's actually not to bad.....but you do feel the weight of the car......let's put it this way, it was better than the Turbo Territory and Holden Adventura I test drove when I started looking for a new car.