For those interested in the SCSI option, it did definately exist (I have it on mine) but you'd have to be really lucky to find one now. If you do have it on your S-550 you may be interested to know that it works with 100Mb Iomega ZIP drives - this gave mine a whole new lease of life (=80 floppy disks & utilities). There is also an updated OS that lets you load individual patches into it instead of whole banks and there was a CDROM drive with the whole Roland sample library on 1 CDROM - anyone got a copy I could borrow?

My sum up would be that nowdays it makes a good "instrument" based on sampled waveforms, if you just want to replay drum loops or found sounds forget it, there just isn't enough memory. Also I seem to remember that although it only had 12bit A-Ds the D-As were 16bit and it did some sort of interpolation.

Finally got a monitor and realised that it's not difficult to use at all, you just need to be patient.

The sound quality is 12-bit but that's nice if your'e into that but you do loose a fair bit of top end.

Not much sample memory but it goes a long way if you use sub tones for different filter/LFO setting etc. Overall you can do a lot of things with it especially as it comes with eight outputs as standard which are all pretty quiet.

I've heard people complain about the lack of real time filter cutoff control but on mine you can assign aftertouch to the filter cutoff. So by drawing controller maps (or mapping controller 1 (modulation) to aftertouch in real time) in your sequencer you can create some nice effects, but this only works for the low-pass filter. The high pass is a weird one that just affects the whole sample uniformly.

I like it, I like the price, like the sound, like the filters, like the LFO and even like the operating system but don't like having to take the monitor everywhere. No time-stretch though, bugger.