I just put a Nytro skid in my RX-1, I mounted exactly in the same position as the Apex Mtn Tunnel (skids dimensions are the same except for rail length) and the last 16" of the track doesn't touch the ground. I have the Apex 162" skid in my other sled (RX-1) and it seems better. It seems like the "tipped up" portion of the rail is more on the 153" skid than the 162". Anyone with pics of their Nytro on flat ground that I can compare? I made sure limiter strap and shock/spring settings were the same, even matched the front spring pressure.