I need two boxes to go under the back seats in my king cab titan. Was thinking of trying the RE SR's. I've used the RE calculator to build a box that should fit, I'm just not sure if it would sound as good as I think it would. It seems to be small at .74cuft tuned to 34 hz before sub displacement, AND using 1/2" mdf If that isn't going to work then I guess i'll stick to a sealed box. the amp gives a rated 780w RMS to 1 ohm. Opinions?