no way 2 comp vr's12's would be louder then 2 12w6v2's. if both were given their rms and in similar boxes. i have heard both sytems and the jl's will get louder. now if the question was if 4 comp vr's is louder then 2 12w7's that is a more fair match up w/ the right box the w7's would be louder then 4 comp vr's. i would bet that 2 w7's would easily get louder then 4 comp vr 12's
p.s i'm sorry i'm just not impressed with the kicker comp vr subs i have heard them many times and have been thouroughly diassapointed w/ them. i'm not saying their terrible i just feel they're a little overhyped.
I had 2 SPL mules in vented boxes set up for SPL and managed to hit 150.6 with 600rms watts. A guy at that show with 1 12in W7 in a vented box being fed off of a BD1500.1 hit 153.1 but burnt his sub pretty bad while doing this (still kept playing but stank). I now have a CVR in one of the vented boxes the SPL mules were in and it doesn't compare to the mules. The Kicker subs have went downhill in the past few years, I'm not impressed with that CVR nor any of the recent Kicker offerings I've heard. Check out Credence they still sell the Kicker comp D's (original VRs) and the old round solo barics still made in the usa (just look up Credence on google) if you want to stay Kicker. To answer your question I'de imagine the W7's will sound better and be louder than 4 CVR if set up similarly.