I have this brace in my car...
http://www.do-blog.jp/hks-tfh/article/458
http://cs-marche.com/
I went like...
Stock
↓
Low down spring
↓
Coilover
↓
F&R tower bars and F&R under braces and roll center adjuster
↓
Fender braces
I could feel improvement each time I upgraded. But this parts is not too cost effective(about $200)