The DX cluster works like a charm using the built in TNC.
even with speech.
It will anounce call sign and frequency only, and can be set to
automatically switch you to the frequency that shows on the dx cluster.
This can become pretty amusing when there is lots of activity and the rig is
madly switching frequencies everywhere between 160M and 2M.
You can easily stop that process though and stay on what ever band you wish.
The local DX cluster frequency here is unfiltered so i get everything from
china to down the street as far as reports go.
Most places i suspect have filtering options to allow for only signals heard
from their general geographical region of the world.
I have never used the TNC for anything else such as packet operations or
APRS operations or sky command, but i know it works really well.
Also, most modern satelites are still on VHF (144-146MHZ) and UHF
(430-440MHZ)....usually UHF downlink and VHF uplink.
very very few are using the 1.2GHZ band.

As far as antennas goes, the up and down roter part isn't as necesary for
satelite work, that is more for moon bounce or E M E communications.
With a good VHF  UHF beam cross polarized or just horrizontal, you can very
easily work satelites.
there are a few brands that are vhf/uhf dual band beams that are used for
satelite work.
73
Colin, V A6BKX