I switched from Scottish Power. It took a year to finalise the bills from Scottish Power, through a seemingly interminable saga of failed computer systems lengthy phone calls and confusing and erroneous statements. It took less than a week to have things sorted with Good Energy. Eventually the matter was only resolved when Scottish Power had to ask Good Energy for another copy of the changeover information because the Scottish Power system had screwed it up, at least that's what they told me, though given the mess of everything else to do with Scottish Power that may be another fairy tale. Thank you Good Energy, please keep up the good work.