I looked into this a while ago. There was an article in one of the broadsheets sponsored by a company called VPhase. They reckoned that you could save upto 10% electricity by installing one of their units. I found a Australian "paper" where they debunked the whole thing, if I can find it, I'll put in a link. Essentially the only gain would be in lighting, but if you go for low energy or low voltage lights that would nullify any benefits. The regulations state that the supply should be 230v+10% -6%, the rest of Europe is +/-6% (+10% means that we don't have to alter out voltage from the old 240v). I checked my supply it is about 257v, not sure what I can do about it, don't think the supplier will alter our local transformer.
