If you love the game, buy the original during a Steam sale (Unity often drops to $5.99). Use the compressed version to save storage if you already have a license.
Maximize Your Play: Is ‘Assassin’s Creed Unity’ PC Highly Compressed Worth the Storage Swap? download assassin-s creed unity pc highly compressed
Assassin’s Creed Unity is infamous for its terrible PC optimization at launch. Even today, on mid-range hardware, you may experience stuttering. If you love the game, buy the original