Tek,
You are right about the memory, sorry I had a long day working with medical terms.

The reason I said "advertising" is that I see "workstation" being used loosely by those marketing them. I have 3 keyboards, all 3 has a sequencer, midi connections, and all the other things you mentioned. Only 1 of them is a synth having the capability of synthesizing a sound. That keyboard is complete to the point that if you so choose you could do anything with it as a stand alone instrument except that it has no amp or speakers. My daughter has a "workstation" that cannot be classified as a synth. It has a sequencer I certainly would not like to work with. Therefore it appears to me that the term is used in an effort to market the keyboard. I have no doubt that you have/had a keyboard marketed as a workstation.