I had 2 JL 12'' w1v2 subs in my truck for like 3 months and they sounded damn good. They were nice and clean and had pretty good spl, it shook the Titan pretty good. They just cant really hit that deep, they're loud but not deep if that makes sense, I now have 2 12'' JL w3v3's and they definately hit harder than the w1v2. There is really no comparison imho between the two. The w1v2 is a great sub that sounds really good and for the 100$ cannot be beat. The w3v2's are just plain nasty and hit really deep and hard, while maintaining the sound quality JL is known for. Either way both are good subs and you will be happy with both unless you are a serious bass head then get the w3 or you might be disappointed.
Keep in mind that the w1's only need 5 in. of mounting depth while the w3's need 7 in. I had to get a custom box made when I got the w3's and they are a tight fit under the seats in my CC Titan. Get a good amp at least 250 rms for the w1 and 500 rms for the w3's. 4 gauge amp kit.