that is a great choice. I have the equivalent on my W. The difference is unbelievable.I'm hoping to get this before the dragon this year
http://www.corsportusa.com/store/catalog/product_info.php?cPath=1_47&products_id=16513
It's expensive but I've heard good things about Whiteline sway bars
black is '11 STI sway (19 mm) with '11 WRX end link... this is a big upgrade from the '11 WRX sway (16 mm)
silver is whilteline 22 mm adjustable sway (don't recall the end link) ... set at 22 mm
I never had any issues with the progress bar messing with the mounting bracket. I had the bar for 4-5 years, 3-4 years with the Tein coilovers and 1 year on stock stuff.