Augemitbutter said:sigma is the final version of a great game. no reason to play the inferior version when you can get an all out improved package to satisfy all your needs.
no contest.
According to Itagaki, Black was the final version of a great game. I'm not saying Sigma is bad, it's just not the 'definitive' version by any stretch (the opening cutscene is missing for crying out loud). So there is a contest.
Of course I'm sure SOME of the people saying Sigma 'no contest' have never played Black. They are both really good and upgraded graphics is the only true advantage going for Sigma. It's still a port at the end of the day. A really good port tho.
Edit: Here are some other links for thought:
http://www.neogaf.com/forum/showpost.php?p=8571458&postcount=1
http://www.neogaf.com/forum/showthread.php?t=228340