Circuit bent PSS-280 + Speak & Read (Yamaha & Texas Instruments)
How to bend a pss-280 with bonus make out sess.
PSS 380 390 460 470 570 2op FM, custom drums, synthesizer section, 380/390 have hilarious presets like golf, alien, crystal, ghost, 470 570 have PCM drums, 460 has crazy fm drums. PSR 36, full size version of above, MIDI, awesome.
PSS 31 has no MIDI or synth section but is still a decent full size keyboard.
PSS 480 580 680 780, later generation, 2op FM, synthesizer, MIDI sysex. 680 780 have sequencer.
PSR 37 4500 4600 DASS sound source, FM and samples, MIDI, unique sounds like a ghetto TG 33.
PSS 790 AWM, no synthesizer, but vector joystick. Sequencer.
PSS 380 390 best presets and great synth section. Used to have 100s of em at my school. Both are identical except for colour scheme.