Peter: My experience w break-in.......
Right out of the box my BB Xtreme was excellent. You will get a good dose of its character and ultimate sound right from the outset. Certainly not unlistenable like some non-burned gear I've owned. It just gets better with use....mainly in the areas of control, coherency, focus, inner detail and dimensionality. Subtle...not night-and-day changes. Such that I am unable to pin a total number of burn-in hours on it.
Restock: as I've already mentioned, tons of comments and many enthusiastic JM owners on the Klipsch forum. Why not just wander over there for some opinions?