I have heard the SW150 and it's a great little sub. Bass is nice and controlled. The new SW series are a big improvement over the old powercube series; which I found to be on the boomy side and very average.

If Wharfedale is indeed cheaper where you live as you stated; then I would take advantage of that and get as much sub as possible by considering the bigger subs in the SW series....the 12" SW300 and the 15" SW380.