Green Star unlimited tariff...any views?

My fixed deal with Scottish power will end in 5 weeks and I am looking for an alternative. I noted the attractive unlimited energy from Green star but there are hardly any reviews about it on the internet. When I put my details on the site, Green star says I can have the unlimited tariff for £1788/year (dual fuel)which is slightly higher than the best deal I can get through the mse energy club (£1501/year) but I like the idea of unlimited use. My current deal with Scottish power cost me roughly £1400/year but this is with very tight use of heating and electricity (I know it is a lot but i live in a large 100 years old house with a 40 years old boiler and we will be renovating soon).

Any ideas or first hand experience about this Green star deal please.