i have 18 receivers on my bev... they said the limit was 6 i believe, but i just keep adding 'em on and they don't say anything... i got my whole family running off my account and a small apartment building, too.
i use the multi-switch papi describes... works great for my hd pvr system
for all the other places i use a 6 way (that is amplified through the coaxial cable) at the apartment and the family units don't need any splitters, just use dual lnb's which i think they all are now...