Ask HN: Xamarin for cross-platform development?

Is it a trap?

So a team I'm advising is deeply invested in Xamarin. They'd ultimately like the dream of a single code-base for both Android and iPhone. However, Xamarin is organised such that the device specific libraries quickly out-strip the functionality of the device agnostic library, so a large portion of the code is now device specific.

A spot of research reveals that the popular advise is move from MVC to MVVM, and attempt to isolate the device specific code in views thereby minimising device specifics.

My question is does it actually work given realistic time pressures and business priorities, or is it a trap?