Features  
Year Made 1989
Original List Price $?
Polyphony 31
Mulitimberal 6
Tones & Patches 128 tones 64 patches 64 performances
Type of Synthesis Digital PCM Synthesis
Effects Chorus Reverb
Sequencer or Arpeggio none
Drum Sets 4
MIDI programmable 1-16 for 7 instruments
Outputs 6 - Out L & R, Dir 1 L & R, Dir 2 L & R
Backup Memory Card MIDI sysex
Options Sound cards

 
My Comments
I've been wanting to retire the U-20 for some time now, but I also wanted to get a U-220 at the right price. SO I waited and finally one came my way. I quickly found there are some minor differences between the U-220 and the U-20. The first is fairly obvious, a second set of direct outputs. The other is the way the velocity for each tone is set, in the U-20 it is a range between the low note and the hight note set by you. In the U220 it is set by a threshold and sounds either below or above the threshold.
 
I rate it 
I bought it for 100$ c
I owned it from jul 2015 - present
Current PrePay value ?$ us
condition of my keyboard
cosmeticaly  Looks good.
electronicallyEverything seems fine.
Status
2016: Sitting in rack 2 with the Orchestra and Ethnic cards inserted. The sounds are starting to diverge a bit from the U-20.

2015: in the new rack.

 
Resources

Factory Presets - Here is a SYSEX file of the Factory Presets.

U-110 cards - a table of the U-110 cards with comments on the ones I have.