So not only will owners need to replace batteries more frequently, but starter motors as well x_X
I have seen no evidence that owners have needed to replace starter motors or batteries more than on traditional cars.
I agree that the system that stops the engine at a specific point in crank rotation sounds more graceful, though I wonder how well it works in practice and what its effect is on cost and maintenance requirements. Do you have any technical information on how it works and what kind of parts are required?
I've heard of some cars needing batteries sooner in Europe. There were complaints on an overseas Kia forum. These systems do improve the numbers on their tests. So manufacturers could skimp on the system just get a better number for cheap, in theory. Manufacturers in the US will get a credit or something to their CAFE numbers by selling start/stop systems, but they have a small impact on the window sticker numbers.
Ford has been selling their system in the Fusion for over a year now. Which is about how long batteries were lasting in those Kias, and I haven't heard of any complaints with the Fords. If worried you could put a second battery with isolator into your car like GM has done. I think the Malibu has a partial electric AC, and thus higher accessory load than atypical car, though.
The only starter dying early I heard of was the one on Wayne Gerdes Accord. That wasn't an automatic system, and it involved more stop/starts than any of these factory ones would add to a starter. Which is likely a heavier duty to begin with.
might want to check these out, they are CARS! eliomotors.com . You can buy one for less than a used car and it will be brand new. Production is suppoda start next year and 84mpg is a nice number for $6800. Seats 2 BTW.