Took it out again today. I'm pretty sure it's the saddle change that's making my knee unhappy, so I'm going to have to go play with it again. Much less butt soreness than after mile 15 on Friday. My wrists and arms are much happier this time. I'm still finding myself shifting around a bit to give my sit bones a break. This thing is quite hard compared to the SI.

I'm still not sure how well the 143 works for me width-wise. I'm only getting soreness in my left sitbone, which is kind of odd, but I know I sat on the SI weirdly (even DBF pointed it out). I'm going to give it another couple test rides and see how well my sitbone copes.