"The question is whether the rest of britains dissatisfied voters will go Lib or Ukip."

That is too anglo-centric a take on it though. UKIP are only standing in less than half of the non-English constituencies in the forthcoming elections. They have no presence in Northern Ireland and I'm not sure about Wales but in Scotland they are pretty much an irrelevance to the overall results. The Lib Dems are relevant but I don't think there is any sign of a swing to them and they'll probably end up in 4th place here as far as overall votes go and might even lose seats. The main issue here is more how many people who voted SNP in the Holyrood election will vote SNP in the Westminster vote? The polls so far suggest Labour are doing well.