They were good, but have been absolutely useless with my gas. My gas meter was broken and I couldn't get a reading, they decided it was reasonable to charge me double what OFGEM recommends for a house my size, this obviously put in into the negative, charging nearly £300 for gas and electric each month and they still were saying I was using more than that. Finally got the meter fixed in July, showed them a breakdown of how much I actually use, as well as submitting meter readings. I was told they would manually review my account and should be sorted by the 10th of October. I emailed on the 10th and I've still to hear back, nor has anything been updated (or a rightful refund been given). I've just changed my tariff so I'm not hit with more insane price increases and they've made it that I have to pay an extra "catch up payment" until March next year, making me pay even more now than I was! I'm absolutely furious and would seriously advise against going with octopus if you think you'll ever have anything to wrong with your gas or electrics (although we all hope it doesn't). I thought they were meant to be good with customer service but it's been lackluster and I've been left waiting for weeks at a time with no correspondence.