Sorry, must have missed this question. Thansk NC Flamethrower for bumping.
Nike Shox, while certainly very stylish, were not designed to weight train in. The design of the shoe forces the heel to be elevated in relationship to the toes. It creates a mini "high-heel" like effect in the wearer.
It is almost impossible to squat correctly in Sox, even when it seems like you're doing eveyrthing correctly. It places undue stress on the knee and places your body at a mechanical disadvantage. In addition it forces the body to lean forward slightly, throwing off correct posture. And anyone who has read any of my material knows just how vital posture is to performance and safety.
The best shoes to weight train in are flat-soled sneaker. Skate shoes such as DC's and Vans are great for this. I personally use DC's when strength training.