I have handled both the Steeda and the BMR braces. The BMR is clearly a more solid, stronger, item.
There is a past thread about these parts here, including a very good post by Chevykiller (and F1Fan) that discusses them individually:
http://www.mustangforums.com/m_1481499/tm.htm
Keep in mind that if you get any of these braces, you REALLY need to have them welded in place. Bolting just doesn't cut it.