I've finally got them setup the way I think they sound best.
They produce excellent bass. They sound a lot larger than what they are. The CP108LG-W3v3 is a well engineered, slot ported enclosure loaded with a 8W3v3. There 250w RMS rated each. Although my two 12" JBL 1202Ds in sealed enclosures on 150w RMS each, had a little more thump in the lower volume range and less distortion when turned up in the higher volume range.
The bass output from these little buggers is incredible. I've never heard a pair of 8s sound this good. In fact, the JL dealer that installed everything said the same thing. Today I brought my truck to a different audio dealer/installer, for a front stage install qoute, and they said the same thing. They were pretty amazed by the sound from such an insanely small enclosure/sub combo.
I would recommend this sub to anyone seeking high bass output in an extremely small space. They're about $200 each. That's one of the more cost effective loaded enclosures out there for small spaces.
If I could do it over again I would probably but a single JL 13TW5 and run that off my 500/1. Just for the cleaner look. I would be able to mount my amps on the rear wall with the subs. My current setup doesn't allow this configuration.