Is there any particular reason you need IPv6? I get the whole IPv4 exhaustion thing, but if AWS can figure out a way to get me an IPv4 address when I need it, this seems preferable to dealing with IPv6.
IPv6 is provably faster, especially for mobile clients. iOS 9/10 also prefer it and the App Store has begun requiring apps to work on full v6 stacks, meaning any end points in AWS will require 6to4 somewhere.
