Here is some more detail for you, Crespo: CorkSport
Stiffness: adjustable; 135% stiffer than stock, 190% stiffer than stock, & 260% stiffer than stock
Color(s): blue or black
Price: $199.00 + shipping
URL: CORKSPORT Mazda3/Mazdaspeed 3 Rear Adjustable Swaybar James Barone Racing
Stiffness: adjustable; 593 lbs./in., 718 lbs./in., & 901 lbs./in.
Color(s): red w/ silver logo or black w/ red logo
Price: $195.00 shipped
URL: James Barone Racing Racing Beat
Thickness: 1.0625" (27mm)
Stiffness: not adjustable; 3.24 times stock
Price: $157.00 + shipping
URL: Racing Beat Tri-Point Engineering
Stiffness: adjustable; 750 lbs./in., 825 lbs./in., & 1000 lbs./in.
Price: $206.50 + shipping
URL: TRI-POINT ENGINEERING
NOTE: According to the Hotchkis website, their RSB for the 1st gen. 3 is not compatible with the 2010+ models.
Please let me know if I missed any, and I'll add them.