I have used this wireless phone jack system to connect a DirecTV receiver for over 18 months (and for three months, a Tivo) without a problem.  The stations are about 20 feet apart with a wall and furniture in between, but I have not had connectivity issues.  I have two wireless networks (b and g)in the same area and have not had the interference problems others have mentioned.  That said, my parents tried using the same system in their home and got lots of static and dropped modem connections over a 15 ft. line-of-sight installation with no other wireless networks, so the system seems to be somewhat picky.