I'd only put a quick release on it if I was sure that everyone who used it was going to lock up their back wheel (I'd encourage the Sheldon Brown lock strategy [1]). Most people lock the frame and maybe the front. This back wheel would make up the majority of the cost of your average bicycle in the rear wheel alone, making it easier to steal isn't the best idea. Maybe ship it with a nice hex wrench to make taking it off easier, but a quick release on that would be a bad idea if you're marketing it to cycling novices.
I know if I got it, it'd be pitlocks all the way. My commuter is barely worth $500, this would double what it's worth in a single easily-removed part.
Also, I don't think a quick release will work for this. The motor needs to push against the bike in order to move the wheel relative to the bike. A quick release will slip.
Also 10 pounds is a huge difference not just in the effort needed to propel the bike forward but also in terms of maneuverability, especially as it is rotating weight. And in city usage you often have to carry the bike down stairs etc. where again 5 kg and a messed up center of gravity is a big deal.
Look more closely at your bicycle. The axle doesn't turn in the dropout. Rather, the hub shell turns around the axle. That's why the bearings are mounted in the shell rather than in the dropouts.
Actually I think their pill-shaped peg that slides into the dropout but won't turn within it is kind of brilliant. A very simple solution, and there is no reason it couldn't accommodate a quick release skewer.
I agree that bicycle weight is a fairly minor consideration for commuting in moderately hilly areas; I've ridden a longtail that's close to 50 lbs. for years. Maybe I don't notice the weight because I am a fat bastard.
http://sheldonbrown.com/sturmey-archer_tech.html
Remember Newton's law of motion here: for every action, there is an equal but opposite reaction. As the motor drives the wheel forward, the resistance from the street will try to spin the motor backwards, causing the hub to spin in the dropouts. That's why a quick release alone isn't adequate for internally-geared hubs, drum brakes, or motors.
http://www.blogcdn.com/www.engadget.com/media/2013/10/flykly...
You are not alone in having bicycled and taken physics!
>>Stress the ease of hot-swapping that wheel in even more than you are now. This is a major selling point.
These points are really crucial. A true pedal assist is something that can assist you while it can, and then not make it difficult for you to pedal when it can't.
Besides, I feel this market has immense potential you could do amazing things with a good control system on that smart wheel. And probably some day even an ECU.
5 kg is light for a battery/motor module, but it still adds about 50% to the weight of a decent bike. The added thickness also means it's probably not practical to put a multi-gear cassette on it. End result, this will cripple most bikes once the battery runs out. More weight and poor gear ratios = hell for the cyclist. However, most smart-bikes are crippled anyways once they run out of juice.
The great thing is that you can use the same bike for commuting that you use for your sweatier, long-haul weekend trips. All you have to do is swap the original dumb-wheel back in. If you buy a dumb-bike and a smart-wheel you almost get two bikes for the price of one.
Tip for the makers: Stress the ease of hot-swapping that wheel in even more than you are now. This is a major selling point.
P.S. I don't see a quick-release clamp on this sucker in your pictures or video. This is a no-brainier and absolutely needs to be on there.