It's cheap, multitimbral, velocity-sensitive, has reasonably listenable sounds, the keys have a good feel, voice robbing isn't as bad as most other Casios, and it responds to the basic MIDI controls sent externally.
All in all, I'd recommend it as a first synth to people without money to spare who don't know of any used-instrument stores. Keep in mind, though, that you'll NEED to use headphones or external speakers - the built-in pair is the worst I've ever heard.
It would have made a decent extra controller if they had bothered to put in a sustain-pedal jack or MIDI octave-transpose buttons.
Try the "Samba" rhythm - it's deliciously terrible.
Random neat perk: The percussion map conforms to General MIDI, and the keys are labeled with little pictures of the instruments.
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