I don't believe that MOG has any significant uphand on Spotify. I did a little research on the web. Anybody know for sure differently?
Here is the response I got from Spotify regarding higher resolution files:
The majority of tracks in Spotify are of a high-quality at 320kbps, apart from a small portion of our catalogue (less than 5%), which is currently only available in 256kpbs.
As for your mobile, 320 kbps is available under the setting of 'Extreme Quality'.
There's more on this here: http://www.spotify.com/help/faq/tech/codec-quality/
If there's anything else you'd like to ask us, just let us know.
Otherwise, have a... http://open.spotify.com/track/6Pi1WqBTTSjtl6BWHQSccH