They are legit but AUD600 for an Edge 1000 doesn't seem super cheap to me- it is unit only. that's about S$700, I paid S$625 for an 810 bundle from Parisilk. I looked at the Edge 1000 when I replaced my stolen 800 a few weeks back and I wasn't super impressed. Firstly it is considerably bigger than the 810 and the 810 is already on the upper limits for me on size for bar mount stuff. I don't bar mount my Iphone I carry it in an arm band Secondly the added functionality is not worth it in my case - I don't need to send real time data via an Iphone to Strava etc end of ride download is fine. I don't really give a shit what gear I am in as long as it is the right one! so the comms with Di2 are pretty meaningless. Plus it doesn't have really usefull features like bike profile that the 810 has.
About the only selling point was the higher res screen but for my needs the 810 with OSM works perfectly well enough and not sure how that will effect battery life - the rest of it seemed a bit gimmicky to be honest