I am considering upgrading my sub following a recent speaker change.What I want advice on is would I hear a reasonable improvement over my current BK with a budget of £1000 max.? The sub is used exclusively in a stereo setup and I listen to a lot of bass heavy music but also have a pretty varied taste. Thinking I`ve been struck down with upgradeitis as I`m pretty satisfied with the BK but as always can`t help wondering if it could be bettered!