The Sigma sports Rox 8 comes with a barometric altimeter. After my ride today I compared the reported ascent. Rox says 1177 versus 1002 GPS. Given how inaccurate GPS altitude is, I'm inclined to take the Rox numbers. One nice benefit of Rox8 is that it shows the grade during the ride.
Overall, I'm happy with the Rox8 and how it performs. I especially like downloading the ride to my computer.
