How the different sized enclosures react in the car will also make a difference.
Did a 2 18 set up in a tahoe, 54 legal and impressive on music, peaked at 39-40Hz. Did a new box with 4 18's, same number legal, peaks at 34hz and moves a TON more air on music. Both boxes tuned to 36Hz...
For a daily/demo set up I'll always take cone area/motor strength over less subs with more power.
Did a 2 18 set up in a tahoe, 54 legal and impressive on music, peaked at 39-40Hz. Did a new box with 4 18's, same number legal, peaks at 34hz and moves a TON more air on music. Both boxes tuned to 36Hz...
For a daily/demo set up I'll always take cone area/motor strength over less subs with more power.