Yesterday I obtained DDR Konamix. I passed all the songs at some reasonable level. It's a bit different from DDR Max (US PS2); it seems to be much easier to score "perfects" on Konamix. Furthermore, every single score i received was a "B" or "C"..."B" on songs that i do ok or well on, and "C" on songs i barely passed. For example, i just played a pretty easy song, got 158/18/1/0/0...one away from an "AA". The grade on it was a "B". The scoring system is quite... different.
EDIT: Aha, I see. In Konamix, you can only get an "A" by full-comboing a song.