I was wondering i was reading some stuff and found a thread on another forum a few days ago about how someone was upset that they could not use satalite radio tuner and an HD tuner at the same time i forget wich system it was maybe it was a clarion or a Kenwood i forget

but is this true on pioneer also ?

or can we have both hooked up ? at the same time

Yes we can as far as I know.

almost all of pioneer add on devices have a pass through IP bus connector, so that you can use both. this is true for the xm tuner and the HD tuner.