I have had one for several years now, and yes, you will have to adjust it from time-to-time; either the channel or the amplitude of the current channel.
I have warned about this in the past:
* Be sure you understand the interface of the external device. In the past, it was not so obvious how it worked, making it too easy to turn off the internal device. Read the instructions carefully.
* When leaving one channel to go to another, turn down the amplitude of the current channel first. For whatever reason, going back to a previous channel that you could not even feel will feel intense if you later go back to it.
* I'm sure your doctor told you that you have up to 99 programs available, but mine only holds 4 at a time. So you can ask to have it changed to something else.
* Also, don't turn it up above about 4-5 for long. Doing so will drain the internal battery. That will have you back in surgery to have it replaced often.
God bless you.