We've just changed too. 10% in year one, followed by 5% in 2 and 3, as others have said. Stated to be 10% under ESB even if they counter by dropping their charges. We can leave at any time, and while ESB might levy some switch-back fee, it would probably be counter-productive for them to do so.
Only one downside for us - we lose the budgeting facility whereby our monthly payments are evened out automatically over the year. Now we'll pay the cost of the last two months be it high or low. Still worthwhile, though.
Left the cancellation waiver box unticked on the online form so we can back out over next 7 days if ESB make any radical announcements...