There are two skystars 1 -
One with CI module is nothing just rebranded TwinHan VP1031, with software mpeg decode and so on.
Original
SkyStar 1 has hardware mpeg2 decoder (only actual if you have pentium 2/3) and tv out.
Original
SkyStar1 is limited in Symbol rate (range is 8000-30000 afaik), while
Skystar2 can handle 1000-45000.