King Ranch to be honest(not trying to be rude) but you just need to pick one and try it.
You may like the sound of the L7/CVX/SX etc.
All the subs discussed are good quality(although I dont like the L7), but do have potential depending on a lot of variables.
Like I said do some reading on what ppl think(as you have now) and then go with what you feel will be best.
Worst thing that comes from it is you test the subwoofer out in different enclosures and if your not happy, then trade/sell and go a different route
I do wish you luck sir and do think of the choices that you would be happiest spending the extra $$$ with going the SX route, or maybe finding some used BLs