Quoted from Davi:
The Pinsound board plus Pinsound 2.1 speaker set is already shaking the house and sounds crystal clear. What's the benefit in this case?
In this case (the last few examples above), guys who already have an aftermarket sound board are going with PinWoofer rather than spending on the same speaker only upgrades. They are pursuing an outstanding pinball audio experience.
Many don't have a sound card upgrade, so the PinWoofer kit takes the stock DCS sound in a pin such as INDY to the next level (key point - any pin is compatible). It is a huge improvement to stock sound for those that don't want to top out at a $500, $750 or greater price point. You can get there with PinWoofer for a fraction.
Beyond that, the PinWoofer super kit has excellent speakers and two amplifiers, albeit for more than speakers alone, but we feel it is well worth the extra money. You'll get greater power output, no audible low voltage droop sensitivity (i.e. no voltage faults resulting in cut-out during high intensity hits) and immunity to aged driver board supplies. Plus you get end to end technical support and fully documented instructions with photographs.
There are as many combinations as opinions, and if guys are satisfied with their setup so am I. Just sharing my opinion.
Thanks for the question!