Which subs are better?

.I have a Rockford fosgate r500-1that puts out 500 watts rms at 2 ohms. I was thinking of the jbl gt5 12inch or the infinity reference 1262w. I will be getting a pair of them. I was just wondering which one will hit harder/lower. I have two alpine type e10s and they just don't have enough bass. I was also wondering because I have one jl audio 12w1 if I should just get another and that might be better.