Just picked up a brand new set of xfl 10's in trade. I'll eventually be doing a 4th order for them , but they are so stiff from the factory I don't think I fan get enough extension in the low end in the sealed portion of the fourth to break them in. So I'm going to build a temporary box just to break them in for a month or two. Has anyone had experience with these thinking around 1.25-1.5 cubes each tuned around 30 just to help out with the break in. Then I'll grab a cheap set of tens and use the box in my wife's car.