Well - yes the Outback is Faster then the Liberty. The Liberty is one of Bowtechs slower bows. The Outback is a fine bow, and I am not trying to sway you either way but remember - the Outback weighs about 1lb more than the Liberty - So bare bow it has an advantage in shock / Jump / Vibration etc. Get them the same weight then test would be a fairer comparison.
Good luck - they are both winners