What worries me about this a/c is its lack of true redundancy. Its all electric so whilst there is plenty of back up generating power, at some stage in a failure situation busbars have to be linked to get a system to work. Hence the potential for contagion. A/c to date have had effectively three separate power souces hydraulic electric pneumatic, these can back each other up through power transfer units etc, which do not lead to contamination. One only has to think of the tremendous care that say New Yorks power system has been arranged and yet a simple failure can lead to its total shutdown.