Having recently let my Peugeot 3008 (GT Premium Hybrid) drive me to Devon and back on the M5 and A38 dual carriageway without having to use the accelerator, brake pedal or steering more than a few times, I would say that semi autonomous cars with radar assist (steering, distance control and braking) are a real advancement for drivers like myself. I arrived in Ashburton after an almost three hours journey fresh and relaxed having completed a trip that I had previously thought was beyond me.
A light touch on the steering wheel and indicating to change lanes very occasionally was my only required input.
In my opinion fully autonomous driving will be a safer way forward eventually, given the antics of some drivers that I see on a daily basis.