how much offroading do you plan on doing? if its a normal f150, it is definitely a good cheap option, but i know that with the offroading we do in our trucks, there is a good chance that the woofer will fall. being a down firing box, any landing puts additional stress on the screws that hold the woofer in place. the weight of the woofer is working against you. im not saying that it will happen to you, but it is something i have seen before. you might want to add "T nuts" to the box to mount your woofer in place. it will help reduce the amount of stress on the screw holes.