This is what I'm using.

12" Shallow Mount Subwoofer


Size 12"
Woofer Cone Material Composite IMPP using Interlaced Carbon Fiber and Ultra Long Glass Fiber
Woofer Cone Design Double Cone with Air Suspension Control System
Surround 3-Layer Fiber Woven Radial Surround with M-shape Cross-section
Voice Coil 4 Layer, Long Voice Coil
Voice Coil Wire Copper
Voice Coil Bobbin Glass Cloth
Damper (Spider) None (Air Suspension Control System)
Top Plate T-Pole Yoke
Projected Pole Yoke with Vented Pole
Magnet Construction Strontium
Basket Design Cast Aluminum Basket with Fin-Shaped Design
Gasket Rubber
Wire Terminals Spring Compression

Specifications
Watts MAX. Music Power 1400 Watts
Watts Nominal Power Handling 350 Watts
Frequency Response 18 ~ 1,000Hz
Sensitivity 88dB
Ohm Rating 4ohm
Recommended Enclosure 0.5 ~ 1.0Cubic Feet
Dimensions 13" x 3-7/8"
Mounting Depth 3-1/4"
Accessory Grill UD-G306

As for the JL one, I have some ideas i would like to play with, only if i had the extra cash to get a pair! =P