Like many of you, I learned to fly my CX2 well and have had a blast with it indoors and outside, even in wind. I have done a few upgrades to it and I rarely break a blade any more. I bought the CP Pro about a month ago and went through the usually crashes and frustrations. Finally using the advice on this forum, I am hovering entire packs and I look forward to removing the training gear soon. Here's what I have learned.

1. It is essential to test, trim and balance after every crash or rebuild or new part. All you need to know about this is on these forums. A pitch angle gauge and gram scale are very useful. An easy way to check the center of gravity is to balance the flybar paddles on two empty tall beer bottles. Use a ruler along the tail boom to adjust the battery until it hangs level. A helicopter that wobbles even a little bit is not right. When the bird is really dialed in, you can tell by the quieter sound and how much easier it is to control.
2. Adding a set of fly bar weights makes a big difference in desensitizing the controls. Also lenghthening the thumb sticks might help.
3. The heavier plastic rotor blades are really impossible to break, but they almost always cut the tail boom on a hard landing or blade strike. Also, since they transmit the crash force elsewhere, you are more likely to bend a shaft or break something else. I am using the flat bottomed balsa ones for now.
4. The stock shear pins are too strong. Even if they shear, they break the center hub and bend the shaft and leave a big burr on the shaft. I grind a paper clip down to 2/3 s of its original diameter and use that with a little bend on each end to keep it in. The one crash I had, the clip sheared cleanly with no damage to anything else.
5. Even a little bit of wind, like 5 mph, makes it very hard to sustain a hover. Try to find a large indoor area if you can. Now I am fairly comfortable in light winds.
6. Don't be seduced by the aluminum or graphite upgrades until you are experienced enough not to crash. It is true that they do not break like the plastic, but force has to go somewhere and in the case of a blade strike, it just means that something else down the line will be bent or break.

Thanks to all of you that have provided great information to us beginners.