He's been trucking around this Casio SA-75 for a few years and he's outgrown the 4 note polyphony. I'd like to get him something that's about the same size (37 - 44 keys) but with 8 note polyphony minimum and preferably much better patches. I can't stand listening to 'grand piano' that sounds absolutely nothing like a piano. Looking at other Casios, they start moving into the whole lighted keyboard thing (which I'm not sold on) and are more octaves (ie, it may be difficult for him to hold on his lap in the car). Battery power is of course a must as are built in speakers. Sub $200 would be nice, but I'm somewhat flexible. Any recommendations? Thanks!