Hey Fred.
I've been searching for a woo advantage for a while and came across the vantage 2016 in a clearance list early in the year. I bought an 11.. It didn't feel like it ripped off the water like the union II, in fact the Union III feels like even more of an uplift, but when you check the hang and height scores on the vantage 2016, it's very impressive indeed. I've not personally had the perfect day on mine yet, but the 11 made 17m in average power conditions.
I bought a 9 shortly after and am looking forward to a full power day on this. So far it's been 100% trusting and stable, no issues and they are very trusting to use if a bit pedestrian in handling compared to the Union III.