Depending on your tire choice the Cay bar might work well and allow the car to rotate more easily in a corner. It is about the same as a M030 rear bar which makes for a well balanced car running 225/255 tires. If you are running 255 square I predict the car will be too tail-happy.
My brother ran with the M030 rear sway on his BSX car to good effect often beating his older brother running a full Tarrett sway setup. I believe some of his overall BSX track records are still standing.
