Which would you choose?

i would go with the with the L7 but i would go for  a 10" instead of the 8"  but if your going for SQ i would go with the W7 thats just what i think

Personally I would choose the 8w7 if both were a total option, but it sounds like you are looking for totally the wrong thing here.  You said your little brother is not looking for incredibly bass, he just wants some smooth clean low end, although the 8w7 and to an extent the 8L7 will do that, they seem like very innefective ways of doing so.  You said you are going for an 8 because you cant afford a 12, yet you are looking at two of the most expensive 8 inch subs on the market, not to mention the cost of powering these beasts would be hefty.  Have you considered getting two 8w3s or a similar 10" sub, they would fit, fit the budget, and sound awesome in that truck.  Maybe consider your options and costs a little more before choosing a $350 8" sub.

But if you can, those little 8w7s are SWEET!