for a driver to work well in a ported cab, it usually has to have a little stronger motor system than for a sealed cab. otherwise, the big increase from the port doesn't really kick in (unless the cab is made unrealistically large).
here is an example of three subs for comparo with the ftw 21 LTE
, 1000 watts into each system.
1. blue line is 21 ftw lte in 10 c.f. sealed.
2. red line is same in mini-marty type cab (~9 c.f. tuned to ~17hz)
3. green line is 64 cubic footer tuned to 16hz.
so what can be seen here is that going ported in a medium size cab doesn't pay a whole lot of dividends, but if you can go to ludicrous size, you can pick up quite a bit of output. I'm actually not sure what the excursion limits on that driver are (specs indicate 3 inch peak to peak which is about 37mm each way). if that's the case, that output or something close to it should be within reach.
while more expensive, the uxl18 is an excellent choice in the larger marty's.