ummm... like dynocoaster I haven't have had cause to use mine. Ihope I never will, but on the other hand, I am just back from a tour where I had the sense of security of having a pump under my backside, so to speak. But it does need to be reliable, and now I guess I am going to have to carry a spare pump anyway. So why bother with the design complexity of a seatpost pump that has built in obsolecence ? On my Speed TR (which I do adore, I have to say) maybe I'll put a thudbuster post in...