I have the 5'4", it has a nice combination of tracking upwind (when powered) and agility. It has very lively pop when loaded and released, more than any surf style board I've been on. You can olie it very easily, it has just right tailkick for that, or something:) It is actually quite stable, no problems digging a rail etc.
This is not a good lightwind board, it performs best with power similar to that needed on a twin tip, but at that point it does crank upwind awesome with confident edge hold-I have never felt overpowered on this.
Construction quality is tits. Came with five high quality fiberglass fins that are sharp edged and slice water very well indeed. Five fin boxes is great for changing things up, though I pretty much run quad on it.
I'm happy with the quality and performance. If it did all this and was better underpowered, I'd give it five stars (can't have it all I guess;), but as a performance oriented board, it's lively and super fun.