The pro has a few probs, but to Century's credit they are on the ball with rectifying them. Problems listed below
1. Skids break easy.
Solution. Century have a new thicker stronger skid available, and it comes with new kits.
2. Tail gearbox rotates on boom.
Solution. New thicker gearbox around key area. Although I haven't seen this yet.
3. Some of the crown gears are very tight.
Solution. Either quality control is low on this part, or they have made a change, as some say theirs fit perfect. If it doesn't just trim some plastic off the top.
4. Tail gear mesh very sloppy.
Solution. Some don't have this problem. Again maybe a quality control issue? To fix it just trim some of the steel sleeve and move the gear closer to the other one.
5. Tail output shaft gets stuck.
Solution. Oil it before use and keep checking it. A drop of oil every flight isn't a bad idea. Also grease the gearbox.
6. Tail bladegrip lets go.
Solution. None yet. So far this has happened to a couple people. Doesn't seem wide spread though. It is a problem with the bearing failing under load. Really a thrust bearing is needed here. But this would require major redesign of the grips. Or maybe better quality bearings.
Thats about it.
As far as how it flys. So far most are very happy. Me included.
The stock motor is fine for sport flying and mild 3D. Flips rolls etc. It doesn't have the power for tic tocs and the like. Not on 3S anyway. The pinion it comes with is a 10t. Seems to be about right.
I am currently experimenting with an axi on 4s. Boyd has tried it with good results. I hopefully will have more info on that on the weekend.
Hope this helps.