Compact Powered Subwoofers

Though 'powered' seems to be redundant qualifier in today's market dominated by Home Theater Systems (just try finding a passive, or 'un-powered', subwoofer online or at your local electronics store!), here are some of the good-quality, powered subwoofers that measure less than 13" wide/deep that I have been taking a look at:

• Velodyne Optimum-8 - http://www.bhphotovideo.com/c/product/587518-REG/Velodyne_OPTIMUM_8CV_Optimum_8_Digital_EQ_Subwoofer.html
• Velodyne Impact 10 SPL - http://www.bhphotovideo.com/c/product/586453-REG/Velodyne_IMPACT_10_Impact_10_250W_Self_Powered_Subwoofer.html#features
• Polk PSW 111 - http://www.polkaudio.com/homeaudio/psw/index.php?s=psw111
• Definitive Technology Definitive SuperCube III Subwoofer Speaker - http://www.definitivetech.com/Products/Products.aspx?productid=SuperCube%20III

Are there any other brands or models you would recommend I take a look at, before I buy?