Mainly the location of smartcard slot, menu-system, screen resolution, overheat issues. Linux embedded system were used in these china-made hardware sets.
Anyway, you don't need these illegal decoders to view for free?
Just buy any legal PC TV tuner PCI card from Sim Lim Square.
As long as it is BT848/BT878 chipsets, there are so many Win9x proggies from Europe websites to descramble the Nagra signals from wall socket.
This was no secret, software decryption were possible during the days of SCV before starhub bought over.
Analog vs Digital, the signals were still on the same analog bandwidth, only adhoc encryption codes were just changed, and update service is no longer serving older analog sets as their machine id was blacklisted.
The reason why going digital is mainly for VOD and EPG.
