The Kawai & Teisco Analog Synths Group

Hi group: I'm new here and wanted to find out if any of you knew of any 
cool sounds to program manually, my boyfriend recently obtained a SX240 
in exellent shape and only got to program the voices contained in the 
owner's manual, he's interested in knowing about more exotic sounds.
The SX 240 is an awesome machine, incredible the range and the 
weirdness of the sounds capable of producing.
He's thinking about selling it because he's got 2 more keyboards at 
home and the space is getting limited but can't decide which one to 
sell, the SX 240, the Korg M1 or the Peavey DPM3.
Any sugestions?
Thank you