There will be no penalties.
SImply turn off the X, then power up whatever it is you are returning to, dial * 228, and press option 1.
Geri O
If you are under the 30 days you can return device and cancel service back to original contract... If you are past the 30 days and if you want to switch back to other device there shouldnt be any penalties because you are allowed to change your plans at any time and remove features that is no longer required, if the device you activate does not require the data package then you are allowed to change your plan to reflect this updated device status.
Out of curiosity, when you reset do you stop settings from auto restoring because the issues you have reported sound like possible software compatible issue?