It's probably best if you select all the issues it gives you, rather than just four. More fun that way, and you'll have to answer on issues where you're not sure about which policy belongs to which party.
I suspect people tend to answer these things according to what they believe to be certain parties' stances anyhow, but it's pretty interesting.
I got over 66% Labour, but somehow managed to go for the Green Party policy on crime (not too surprising), the UKIP policy on energy (they all looked hilariously bad) and the Lib Dem policy on immigration (probably accurate).
Sorry if this has been posted before. It probably has.