the advantage here is the ability to have several (like 8-16 motors) so the failure of one motor isn't leading to a crash). It is the same paradigm shift as whe

the advantage here is the ability to have several (like 8-16 motors) so the failure of one motor isn't leading to a crash). It is the same paradigm shift as when horizontally scaled commodity hardware systems with expected multiple points of failure have almost everywhere replaced the highly-reliable Big Iron systems. Another advantage is the possibility to have the propellers in ducts/shrouds (eVolo didn't do it, yet nothing prevents it) that is not doable for one big helicopter's propeller, thus such machine can fly near buildings/trees/etc... where helicopter can't. There is also issue of control in tight quarters where air flow is hard to predict and is affected by near by objects - multiple electric motors are much more flexible and faster reacting than one big engine+propeller. Like with electric cars, the main issue is "range". It is solvable by having a series hybrid drive (especially once new gas engines specifically developed for series hybrids - ie. higher efficiency and lighter weight at the cost of power band - come to market). While such system willn't beat efficiency of 787 or fly transatlantic, it would be unbeatable for Santa Cruz to Mountain View commute.