Good call there! I checked the manual, and I don't see any reference to being able to use portamento from the keyboard, so it may be a MIDI-only feature. It does have an impressive set of DSP effects -- kind of reminds me of my old PSR-520. What is weird, however, is that I see no reference to any way to adjust or fine-tune these effects, yet in the description of one of the effects in the function list (the 3 band EQ, effect number 37), it describes it as having adjustable low, mid, and high equalization. But I don't see where those parameters can be adjusted, unless that is also a MIDI-only feature.
Another interesting feature is that the Super Articulation Lite feature can be set to activate by the sustain pedal, instead of just the panel button. That allows you to use it while still playing a background accompaniment with your left hand, but then it appears to take away the sustain/damper function of the pedal.