I'm not sure how or why you gathered that from the site, but I fail to see any real objective information that seems to substantiate that judgment. Hell, they guess at the Xmax of the Z based on nothing more than mechanical noise.......LOL. It simply looks to me like they took more time to subjectively review the Z than they did the Xcon. I'm not saying the Xcon is the best choice or a better sub, just suggesting that your interpretation of that site and it's information is a little inaccurate, IMO. That’s fair, it is probably an amateurs interpretation of what I was reading. These are some of the things that made me think the z was more capable. Xcon made mechanical noise. Z had demodulation rings. Z has a pole vent. Z has 8 layer coil. Z has 9 inch spider vs 8. All of those things may mean nothing or maybe something, I don’t really know. Just sounded like a better thought out driver that based on their description was very well built. Just a different design. The Xcon now has a solid pole which leads to improved cooling and greater motor force over it's initial design. It has some very trick spiral CNC machined cooling channels. It also has a shorting ring in the motor, a massive coil, Nomex spiders and sandwiched leads etc. etc.