Now I don't have a ton of experience with these sub yet, I've only had mine installed for about 4 days so take this into account! But I have mine in a 3 cube (1.5 each) ported box each side tuned to 30hz. These things dig pretty low and shake the hell out of my poor windshield. I am hoping to get it metered Sunday to get an idea where I am at currently before I make to many adjustments ( better power, amp turned up a bit, box possitions) but I went with this box because I was told it would do well in this size box and I already had it sitting around from one of my last installs. Not sure if this'll help, but figured I would toss my info out there.
I also know that the box size differs depending on your power too!