well... I own SYB-3 and SYB-5... the SYB-3 sounds like oldschool analog synth... the new SYB-5 sounds more metalic, aggressive, noisy.
goodies SYB-3 : noise generator, autowah, SAW is better than SYB-5.
goodies SYB-5 : LFO, PULSE 2 for robot-like sounds, SQUARE is better than SYB-3.
differences : PWM is based on "square" for SYB-3 and on "pulse 1" for SYB-5. The SYB-5 has an expression pedal input, controling LFO rate.
both have wave shape (normal / reverse) and the four of them are differents ! cool, isn'it ?
YOU CAN HEAR SYB-3 AND SYB-5 SOUND EXEMPLES HERE : http://go.to/kulten
yeah !