the Edge 2000 System is worth it... I have 4 edge pads, and I also have 2 regular pads that I use on a backing plate which even with the aligning tool, it vibrates pretty bad... The Edge pad is completely balanced and does not vibrate at all even if I put the rotary on speed 6... Edge system is easier to use and is more convinient, plus the double sided is really beneficial... I am lucky that I bought the Edge pads for ~$11 each from
Chemical guys when they were on sale...