The US team has not gotten to test these parts mainly because there isn't much testing you can really do. The brace is just a brace and is more of a tuning option, just like the springs. It isn't something that needs development per say. Add a coil and you got softer, make a 3d image of a brace and you got a brace
Now I have tested with softer springs and they have their place so this will be a great addition in my book.
The front brace is something that I still think the jury is out on. What the brace will do is allow for more consistant rough track handling, sending more of the hits to the suspension to absorb instead of allowing the chassis to absorb. I am excited to see if I can make the car's suspension work more with the new brace and where the benefits will be. I feel like the springs it will be a tuning part, not manadatory. I still think for a lot of tracks the stock brace will be the ticket. The trick is to figure out when you get to the track which one will result in a more consistant car.