Pretty sure the spline is identical. Should work fine.

Yes, it will work fine. 105, Ultegra, and Dura Ace all have the same spline and pinch bolt construction and are interchangeable. I use a DA Stages on both the DA9000 and Ultegra 6800 series cranks.

Will work fine. I have that set up on my bike. The $100 pays for a few grams less of weight.

Works fine. I have 105 and switch it back and forth between tri bike and road bike, both of which have Ultegra.

I have the same set up.

Come on... I bet it deflect about 0.0001" less at 800Watts. That shit is important.

The metal itself might be slightly less strong, so it's possible the splines might not be as durable as Ultegra. But swapping it a couple times a year shouldn't be an issue. But I wouldn't swap it a couple times a month.

I've had a 105 crank since Feb. No issues at all. Even submerged it in about 18" underwater on a flooded road. Ant+ does not transmit through water BTW. But picks the signal right back up a few seconds later. My freehub did not fare as well. You don't realize how important a freehub is until you jam the chain for the 3rd time and really want to stop pedaling late into a 4-12 hour ride and realize you can't without coming to a complete stop. It's the 35mph+ descents with bumps that are a real bitch.

---

TrainingBible Coaching
http://www.trainingbible.com

i have been using trainerroad for ages and just got my stages the other day. Did it take you a lot of practice to smooth out the power on your stages similar to trainerroad? I find it fairly easy with TR 3sec power to hover within a watt or two of a targeted figure. Using the stages on the trainer or the road for the first few goes, im having real issues holding a steady power without it jumping around a fair bit. Its on 3 sec smoothing too!

This is genius!

Stages will show you pretty quickly how even and balanced your pedaling is. No masking it. I use 10s power to make it a little easier to pace with.

---

TrainingBible Coaching
http://www.trainingbible.com

Please elaborate on how the Stages shows you the balance of your pedaling.

The more uneven you pedaling effort form right to left, the numbers the number fluctuates by a factor of 2 at a similar overall effort.

---

TrainingBible Coaching
http://www.trainingbible.com