I have a Poly 800-II (has a digital delay added). I find it to be great fun. I think its limitations kind of improve its sound, in a perverse way. The single filter thing is kind of neat, either when you screw up a held note by hitting another, or by playing a run of notes, all filtered by different portions of the same filter envelope. There are some settings where the filter sounds kind of crackly and ancient, a sound which I happen to love (in moderation). Because the filter is analog, I'm seriously considering adding a jack to inject external audio. I also like the oscillators, which can give various gritty metallic timbres.

------------------
Curiously Refreshing music: http://mp3.com/alectroboy