> By the way: I live in Europe and I haven't worked for one single company which would allow their developers to host proprietary source code with a third party SaaS provider.
Fair enough, companies vary widely in their acceptance of SaaS -- though Reviewable has plenty of European customers too. But to clarify, neither Review Ninja nor Reviewable (not sure about Omniref) actually host code themselves: they just access it through GitHub APIs without storing it. You can also deploy Review Ninja (and soon Reviewable) on-premises, though of course that means you're on the hook for administrating the system again.