Sure it will work. When I got my BL5s, I connected them to my AV9000 via Powerlink and digitally to my CD7000. The BS7000 was masterlinked via BL converter to the AV9000. Everything worked perfect. Powerlink is used when you are listening to RADIO, A.TAPE, TV, SAT, DVD (stereo or suround).
It`s possible to watch TV, SAT... in the mainroom and listening to CD in a linkroom at the same time.
I agree with Chris: It`s funny, that you can do this with a twenty years old system, but not with a BS3000, BS4....
Stefan