I don't have any experience with AEG, but looking at the price for the drill/grinder/impact driver kit on the site you linked ($699), you're within spitting distance of many of the name brands anyway... Sydney tools website currently have a sale on Makita stuff, there are a few 3 piece kits there that are actually cheaper at the moment, although not brushless (not so fussed about brushless personally). If you were hung up on brushless, this Milwaukee kit could be a goer:
https://sydneytools.com.au/milwaukee-m18pp3c-402b-18v-4-0ah-fuel-li-ion-cordless-3pce-combo-kit
Longer warranty on the batteries, possibly a touch shorter on the tool - not quite sure how AEGs extended warranty works. Yes, an extra $100, but get yourself down to Total Tools at the right time, and you'll likely pick it up cheaper than the AEG- particularly if you're on their 'insider' list or whatever it is, they've had some screaming deals on Milwaukee stuff in recent months.
The company I work for runs Milwaukee gear on construction sites, and I can verify they can take a hiding from people who just don't care, and battery life is very good with the m18 fuel gear. Also seen a lot of Makita gear being bashed around on site by other trades without issue, and bought some of the higher end gear for home use...
Number of reasons why I chose Makita, always had good life out of Makita stuff, the fast charger suited my usage patterns at home, could get all the skins I wanted without crap I won't use, the drill I got was the most powerful 18v around (until Makita released their new brushless model, that thing should come with wrist braces!), and I didn't want it getting mixed up with the company gear if I take it on site
Interestingly, you don't see much of the other brands on site - Bosch appears in small quantities, don't think I've ever seen any Metabo gear. Our company also has some older Hilti gear, and you see a little bit of that here and there. Every now and then someone has Ryobi or Ozito, or even DeWalt...
By far and away though, it will be Makita or Milwaukee in people's hands.