Most Do-it-yourselfers in the US go with multiple filters. I put mine just inside the demark. Incomming line goes straight to the DSL filter, one jack comes off the top to the DSL modem and the output heads over to the punchdown blocks for the phone. My modem and ethernet switch are both located adjacent to the backboard where all the comm wiring from the house terminates.
Here, the customer is responsible for all the premisis wiring past the demark. I just ran Cat. 5 for phone and network. It was easier to buy 1 big box.

[This message has been edited by Big Jim (edited 10-12-2004).]