Need advise; i am putting a 8 inch sub in my truck. This is the only size that i want. I am looking at 2 brands. Jl audio and polk audio. The 2 that i am looking at ,and getting reviews on are ,polk audio mm840,and jl audio 8w3v3. The reviews on both of these are pretty much the same. The price differents is around $100.00. I will be using a 400 rms mono amp to push them, and put in a sealed box. What is the right choice?