I was on a pump from 2000 - 2007
My A1cs were ok in that period, usually 6.5 - 7.0
I just got tired of "being hooked up all the time" and I also did not like the way that the large plastic needle in my side felt. Probably not the best reasons.
I asked my endocrinologist if it would be ok to go off the pump for awhile. I was expecting a scolding. However, he encouraged me to try it. He said that I should know how to deal with a change like that.
After 3 months my A1c went down to 5.9 using Lantus and Novolog. This was the lowest A1c I had ever had. I believe that I was more careful in that period then I usually was and this may have accounted for the good A1c. They have since drifted up a little.
It was a relief to get off the pump. I have not used a pump since 2007.
Until they make a pump that can monitor glucose levels AND calculate the correct dose, a pump alone is just an expensive insulin delivery mechanism.
I feel that the carb counting inaccuracies, coupled with varying daily exercise levels is what really makes blood sugars fluctuate. And the pump is as affected by this as insulin delivery by needles.