I can only speak to the Sopra 2 and Olympica Nova III but it might help.
Both are fine and I could own either. The Sopra needs subs for bass extension while I felt the bass depth was better on the Sonus Faber. Both are pretty flat sounding. The Sonus Faber has a slight dip (I mean slight) in the presents region and a slight rise in the treble at 10k (on axis) to my ear. Focal seems pretty flat to me.
I think the focal has a bit more detail across the board but hard to say as they were different systems. If both were offered for free I would take the focal and add subs. Without subs I would take the Sonus Faber.
I personally bought the Revel 228be (also needs subs) which plays right with the others for 1/2 the cost. The 228be is flatter than both on and off axis. Had stronger center imagine, seemed more detailed than the Olympica III but maybe a hair less than the Sopra. The Sopra seemed to have a bit more texture in the upper bass than the revels. Mids and highs seemed like a wash. If all were free I would take the Sopra over the Revel as it looks nicer and sound just a hair more alive. But and a big but these sound pretty close and the cost is not close at all depending on your country of course.