Ge0,
Bassbox Pro cannot model one configuration with say 1000 watts and the other with say 500 watts within the same graph. Its a limitation of the program, however here is what two SD4-10 look like on 1000 watts sealedin 2 cu ft.
Here is that JL TW3 sealed at .8 cu ft vs ported at 1 cu ft with an fb of 32 Hz. As you can see, low end extension is much better with ported and within the passband of 30-80 Hz, excursion is also kept in check. When used in conjunction with a DSP to remove cabin gain, a ported configuration makes for one hell of a good high fidelity sub stage and gives you better SPL with less power.