As Dave has mentioned , when I found out[thru experimentation]that the arranger functions while sequence playback is running, solved a big Yamaha problem for me[hand clap]..This feature mutes the parts that the arranger plays[instead of the sequence part] automatically.This gives a variation available to us if you get bored with the sequences..It allows us to play more with the sequences also, you can play accomp as well as the right hand sounds. The combination of the score and lyric window aids in learning to play with the sequences. The vocalizer in "auto" works perfect for my use.I use the flash ram a little differently then most people..I use one registration, this sets up all the important ready to play and sing paramaters for me, the rest of the flash ram[1500kb +]is dedicated to my sequences[ over 40 tunes with lyrics and harmony], I still have 200kb left for styles or other temp operation..Add the floppy disk and I have an average of 30 more sequences on board, that's 70 or more sequences ready to go with no shuffleing of disk, enough to work all night..For a little package, this works pretty good. Roland has boards that do the same things, DisCover 5[unbeatable sequence play] and Vocalizer, E600 drum mix, and features on the VA's, but the PSR2100, with all the goodies at this price, deserves credit,,,and it is a keeper for me....at least till Roland combines the DisCover and my G1000 in a new board....I always push a keyboard to see what it can't do, sometimes finding workable soloutions as I have found with the 2100....