I have heard that the newer xxx's seem to perform well in small sealed boxes, but am looking for some one with experience. I'm really into low end and sq. I currently have a 4 cube box tuned to 36hz w/ 3 4" aero ports that is doing well, but the sq end is not all there. The vehicle is a 1999 toyota camry.

thanks for any help!

SQ in a ported box is decently hard to attain with most woofers. Some do it quite well (SI Mag, SSA ICON) and some don't do so well. For great low end extension and flat response, you're on the right track with the Sealed sub option.