These motors are used in multi-rotor helicopters and planes. The ability to swing huge propellers without a gearbox is a big benefit. Price is lower, reliability is higher and efficiency is greater. The same benefits can all be realised in wheel driven vehicles.
On top of that, because the magnets are rotating in the open air and are mounted on a huge annular steel heat sink, they don't get as hot, so you can push these motors a lot harder than an 'inrunner' conventional car motor. So a smaller motor will give more power.
In a touring car the inline shaft concept would of course work. In my opinion, the real benefits would be realised only without the transmission shaft, with a motor in each bulkhead and no mechanical transmission at all. Then you can use electric overdrive, on-demand oversteer and all the other things that allow the car balance to be constantly fine tuned for the best performance in all situations. And you can put all your gear right where you want in the chassis - dead in the centre.
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