I've got a Diamond Audio D9 DVC 4 Ohm 800wrms I'm deciding between two amps, same quality, 110$ price difference. Only difference between the amps is the more expensive one can run the sub @ 1000 watts @4 Ohms, and the cheaper one can only run it at 2 Ohms. Should I spend the extra $ in order to run at 4 ohms, or will I not really notice a difference between 2 and 4 ohms? Thanks