Having driven a new golf in Europe last year over 4000km's fitted with Radar cruise control and AEB, which is pretty nifty for such a mainstream sub 20,000 euro car.
Now, if this new autonomous technology works as well as AEB does, I dont see any problem as such. I know in Australia it is compulsary for all new cars to have AEB factory standard, which as a feature greatly reduces the instance of pedestrian or object collision, and I have experienced how effective this feature is on a Lexus GS450H we owned. I had a dog run out in front of me on the blind side of a crest ( at night ) I was approaching, the car noticed the dog before I did and hit the brakes before I even moved my foot off the accelerator, the seat belt pretensioners activated, the whole 9 yards. These systems work and pooch lived unscathed for another day!
So an autonomous vehicle equipped with AEB etc should be no different. I am also very familiar with just how much R & D that American, European and Japanese car manufacturers spend on getting these systems right before they unleash them onto an unsuspecting public. I am sure we'll see scenarios appear where the systems can fail, but would need to research what fail safe systems are already present in the systems architecture. I'd imagine they're pretty thorough at the moment.
The only thing I can see that might be a potential problem is when you send the car away and it gets lost because of GPS interference when HK can be very smoggy/foggy, add the additional issue of highrise buildings and narrow streets..( greatly weakening GPS signal acquisition). If you happen to be visiting a building in a GPS black spot, how will the vehicle find its way back to you ?
This wont be much, if any issue in geographies that enjoy wide streets and lower density building infrastructure.