Jumper Cables - use the stock or should they be upgraded ?

I have used the Nordost  Reference Bi-Wire Jumpers and they were a major upgrade over stock jumpers... without doubt. The quality of the speakers you own... and your ears... will benifit highly.

With that said... I now bi-wire my system with identical speaker runs. My opinion is if your speakers have high resolving power...go with bi-wiring. Its a much more expensive proposition ... but the sound quality improves dramatically.  my 2 cents.

chrisr said....." is there a SINGLE speaker manufacturer advocating changing the provided jumpers?"

Well...yes... as a matter of fact,there is...Heres one. And there are probably many more...

From my Sonus faber speaker manual...

BI-WIRING
This type of connection improves the general reproduction quality, and in particular the bass frequencies. This requires two pairs of speaker cables used in the following manner: remove the connections between the terminals (bridges) ( g.11), connect each pair of terminals (high and low frequencies) independently to the amplifer as shown in g.12.