ported most folks stick to the 2.0 - 2.5 cuft range tuned somewhere in the mid to low 30's as for sealed not too many people are using them sealed but ive heard them do ok in about 1.25 cuft
i got two in a 3.5 box sealed and they bang. But im building a ported box for these puppies that should beat the shat outa the sealed one. The sealed box empressed me, it gets really low.