Hello Hellboy
The Wersi OAS instruments (Which by the way have been on the market since 2000, with the software now up to V7) and the Mediastaion are computer based systems built into a keyboard, and so cannot be compared like for like with a hardware arranger, so have a look into computers, softsynths etc to get an idea of how they work. As an example, polyphony is not a fixed amount on these units, and so you have certainly misunderstood the 1024 and 2000 note polyphony.
Tip. Think of the Wersi OAS and Mediastaion instruments as a computer and controller keyboard with the addition of a software version of a hardware arranger.
Hope this helps

Bill