I don't know what the winds are like over in SA but in Perth they can get pretty strong and unpredictable. You may take off in your boomerang which is powered by a 46LA in a breeze and before you know it at full throttle you are standing still or flying backwards! This has happened quite a few times to me and for the extra $40 or so it is well worth getting the AX so then at least you can get some ground speed. If you don't need the power when your learning simply throttle back it doesn't take a genius. For that tiny price difference its well worth getting an overpowered plane that you can throttle back than an adequately powered plane that cant give you bursts of power when you need it. It's especially worth it when you buy yourself an LA, get bored with the power then you have to fork out another $140 to get yourself a new engine. And as I've said before it'll go straight into your second plane wether it be a PC-9, scanner or something similar. If you ask me you are doing the right thing by "over analyzing" This way you can get everyones opinion then figure it out for yourself and hopefully not blow all your money on something you are going to want to replace in the near future. If you jump into the hobby not knowing this stuff then you are almost certainly going to blow your money on some "great deal" that is offered at your local hobby shop.

On your second plane I have had no problems flying my PC-9. I've only been flying for around 6 months myself and i took it up for its maiden myself. I even had a deadstick having no idea about how this thing is going to handle at low speeds but luckily if you flare it will come down to a crawl allowing you to touch down on the back then the front for a beautiful landing. A P-51 or any other war bird is defiantly a 3rd plane. Tail draggers are a lot harder to handle on the ground and most of then have strange wings that don't produce a lot of lift and generally are a pain to fly.