After living with the '07 for awhile now, the filter setup is OK as long as you make sure it is seated correcly on installation. The seal comes from the filter foam edge being pinched at a 90 deg angle between the cage and the inside edge of the airboot, not the a flat gasket surface like most filters. A perfectly flat surface on the airboot flange is not neccessary. Its critical that you make sure the filter/cage is seated around its entire circumference before putting the seat on, don't rely on a visual, you can't tell, get your hand in there and push the edge of the filter in toward the airboot all the way around.
The Twin Air part looks nice because the pins apper longer and would probably help to locate the filter eaiser on installation.