So, I bought a gen 3 Ibike a couple months ago. I bought the wired Pro version for like $420. My reasons for getting it instead of the Powertap Comp were 1) it's MUCH lighter and 2) the $230 difference.

I wish I could post something constructive about it, but I had to return it. It wouldn't work...at all.

The head unit wouldn't recognize the wired speed sensor. It took it on about 4 rides, and it would never work for more than a second or two. I tried everything; moving the sensor, swapping front wheels, reattaching the head unit a couple dozen times, but it never worked. I must have emailed Velocomp a dozen times. They were friendly, but ultimately not helpful at all. And a little patronizing.
So I returned the unit to them. They sent the same unit back to me, with a note scrawled at the bottom of the letter I sent telling me to do a sensor scan. Tried, didn't help. Returned the unit to where it came. This whole ordeal was about 4 weeks. I was without any training data while that unit was on my bike. I have since reattached my Polar CS200 and am back to training by HR. I will think about getting the PT Comp, but I don't have the time to fuss with it right now. My time is precious and the iBike wasted a whole lot of it. I'll never go back to that product or that company. Sorry, you've got one shot to get it right at that price.