The standard clip for the Topeak seat wedge only "just" fits at the back of the SMP rails because of how it flairs towards the back. It will fit and I have one on my Klein with Dura Ace Seat post. However it works better with the Topeak extended mount. The flat stock one tends to work its way loose while the extended one has a better clamping arm. Just as long as you mount the stock mount close to the bend at teh back of the rails you will be fine. For me the SMP is one of the most comfortable saddles made. But my problems were never sit bone related but more of a Perineum issue.