I am using the charger that was supplied with the SP6 and it still appears to make the cursor jump, lag and freeze when charging. Its hard to diagnose as it can go a couple of days with no issue then it appears.
I am waiting for the next time to see if holding the charger cable helps. seems silly but it can create a better grounding.
In general though.... come on Microsoft. this is unacceptable. Like Emilations I am really considering going back to a mac.