vandersteen with built in subs work great the cabinets and slot loading work well. i stand by my comments about the massive and articulate push pull aluminum cone driver in the 5, 5a, 5a carbon and the 7
i suspect that a pair of sub 3 and Treo CT could properly setup do better than Quattro CT but w cables, i think you are a best looking at price parity...
what a cool geek out forest of boxes, wire and great sound, with lower WAF than Quattro....