Some months ago I bought a Ketron SD 1000 B-ware from Thomann for a reduced price. I'm currently going through all of its sounds thoroughly for the first time, and I've also begun to use two great iPAD apps which can control this tiny 1 pound module, which has no buttons nor display.
First of all, the sounds I am really extremely happy with are as follows (in brackets: Voice Bank + Voice number):
Vibraphone (A 12)
Acoustic Bass (A 33) (nicer to me than the very pluggy Yamaha Motif/MoXF one)
Violin / Cello (A 41/43) - very real bow scratch and vibrato!
Chamber strings (C43) - using the upper, VERY lively, better than the MoXF quartet and the Integra SN-A solo strings.
Altosoft and Contralto sax (A 65/66)
Most pipe organ sounds (including soft stops!)
Various accordeons
Classic choir (B 52) - very, very realistic except the very high register
Swing trumpet (B 57) - great attack phase and vibrato
Lounge tenor and growl sax (B 67/68)
Guitars: Hawaian (B105), Rock&Roll (B110 - sounds exactly like the Beatles in 1965), Ac.Stereo (C29), Acoustic guitars from D34 to D38 (one of them is just like the Integra SuperNatural acoustic strumming guitar!)
Hackbrett (C108) and other world/ethnic sounds.
So, really quite a lot of excellent sounds.
Regarding the acoustic piano, I'm not yet determined. Sometimes it sounds a little too bright and pop-piano-like to me. The 'dark piano' is the most realistic one among them.
In some cases one could criticize that dynamics is a little missing: e.g. most trumpets have nice samples, but don't seem to have multiple samples depending on the velocity, and sometimes not even an automatic filter is applied, so that some of the trumpets keep a sharp timbre even if you play them softly.
I already uploaded a demo of 3 pipe organs (
http://youtu.be/UTjO2M2iVtw). I'm going to quickly record more sounds soon and post them in this thread.
About the iPAD apps, I can strongly recommend iMidiPatchbay and Set List Maker to send bank/program change messages to control the SD1000 sounds.