Jam Sessions DS review at Eurogamer.

"Of the DS' major rhythm-action games, only Jam Sessions has made it to Europe with relatively little fuss - Ouendan took its sweet time, and the venerable Daigassou! Band Brothers never made it at all, despite rumours that it was in development for Western audiences as Jam With The Band. Shame, then, that Jam Sessions is ultimately the weakest of the DS' music games, although it's not without its uses. Where traditional rhythm-action games are essentially reflex tests, Jam Sessions is essentially a synthesiser instead, letting you make your own music instead of playing along to preset patterns like in Guitar Hero."

Full Source: Eurogamer