If you're playing lows, you'll be louder with a higher quality amp. I've quite literally tested this. People don't understand how important dampening factor is, in my opinion. My ED amps were fairly large and heavy for their ratings, but there's a reason for that. Wattage is far from the only rating of an amp. Some of the cheaper, higher wattage amps basically just throw the subs up and down in a very poorly controlled way. That causes distortion, and distortion causes pressure issues. Best bass is when the sub is fluid and always moving exactly to the shape of the waveform. That's why box sizes and port sizes matter, too. The woofer is always changing impedance and that ties into the voltage production of the woofer, and some amps just can't handle too much excursion, because they can't control the sub well.