Yes, they are good, but not all of them and they do not sound the same on all keyboards. They usually record the midifiles for the GM/XG standard and then tweak them for different keyboards, but not all the tweaking is perfect (sometimes the choice of instruments or the effect settings are far from the perfect, but I guess that it comes to a matter of individual taste). The styles usually retain the intro/ending of the original midifiles (in variation 3) and this somehow limits their usefulness for other songs.