I've had the Rox 9.0 since early August. I've logged more than 35 rides and 1,200 miles without a major hitch.
1. Three, I'm not sure if you can adjust them, but I think you can.
2. I lost my cadence readout yesterday and couldn't figure out why. It came back about 20 miles into the ride. Other than that, no.
3. True, cadence is not graphable, but you do get average and max.
4. Not sure, but it is very consistent. My max rate is somewhere around 175 and I consistently get 170 to 175 max readings on 3 or 4 hour rides.
5. None. I really like it.