I had a Boston PV700 along with a set of Boston speakers just before I bought my Axioms. I thought the PV700 was very boomy and not very musical. I ended up returning it and buying an Outlaw sub (similar to the STF-3), which has a nice tight sound.

Very cheap price for the Boston sub (retails for $700). In general Boston Acoustics makes some very good quality products but I think their price/performance ratio kind of stinks.