Some technical questions regarding Unity audio compression

Hi, my name is Jonatan and I'm a sound designer working both for Rovio and for my own indie project in Unity, 20,000 Leagues Above the Clouds.

I have some technical questions regarding audio compression in Unity that I hope might be answered from someone from the development team, but if anyone else has insights I'd be happy to hear them!

1) Unity uses OGG Vorbis compression for desktop platforms, but mp3 for mobile. My first question is, what is the reasoning behind this today? As far as I know, Vorbis sounds better at the same compression levels, and is also free to use from a license perspective. I know previously Vorbis was heavier to decode, but according to the threads below this no longer seems to be the case with modern decoders:

http://www.hydrogenaud.io/forums/index.php?showtopic=92235

http://www.hydrogenaud.io/forums/index.php?showtopic=82125

I understand there may also be a dedicated hardware mp3 decoder in some phones which could save performance, but that this decoder generally only works for one single stream, which is rarely the case in game audio.

2) When switching from PC to iOS or Android as the build platform in Unity, and auditioning the audio in the Editor on a Windows machine, will the content I hear be mp3 or OGG Vorbis? The editor says the content is mp3, but I have a growing suspicion that it may still be playing back the Vorbis data. The material seems to sound worse when I finally listen to it on the actual mobile device.

Thanks!