I haven't heard the plus or version 3, but others who have say all three versions sound somewhat similar. The MHDT website says: "Same circuit as older Paradisea with a little different in PCB trace layout."
In addition to USB input, the plus and version 3 have a different opamp than the original. Many say they prefer the original opamp. This forum over at head-fi will give you plenty to think about: MHDT Paradisea Owners Club
If you want more info, check out this forum at Audio Circle: Paradisea DAC
In addition to USB input, the plus and version 3 have a different opamp than the original. Many say they prefer the original opamp. This forum over at head-fi will give you plenty to think about: MHDT Paradisea Owners Club
If you want more info, check out this forum at Audio Circle: Paradisea DAC