We've now officially switched over to Powershop. The range of electricity packages and products you can choose from is not as huge as the advertising might lead you to believe, but I think there's enough choice to make it worthwhile. (Well, any choice is an improvement on the alternatives.)
What I like about Powershop best, though, is being able to keep track of and micromanage our power use. In fact I think I feel a new obsessive compulsive disorder coming on.
Almost hourly I'm on the Powershop website checking our meter reading against the Powershop estimated reading for us, seeing how much of our paid-for units we've used up, and running round turning things off to see if it makes any difference to how fast the units get used up.
I guess the novelty will wear off soon ...