In order to get the best sweet spot in an HT with multiple rows, you need to make sure that your room has plenty of space to the sides and rear of the gallery. Your sides need to be out, away from the side seating. Also, the closer the seating is to the wall, the more the subwoofers will produce bad peaks. With the Ultra II speakers, I'd highly recommend getting the widest possible accoustically transparent screen you can afford/fit and mouting the speakers behind. Also, two subs are better than one!