The child needs to want to go on the pump. If they do not accept it, don't do it. However, if they are receptive to the pump, and you are willing to put in the time, there are few reasons not to get one. Heather figures her own doses, just like she did with shots. And as with her shot therapy, we always confirm both her calculations and the amount of her dose.
Parents are usually the best judges of their children's capabilities.
If you think your child is ready for a pump, and they want it, do it now. You'll wonder why you waited.