Glad to have got some discussion going...
Here is more fuel for your discussions:
1- a demo is supposed to make you think: "Wow! That keyboard sounds really cool: I want one!"; too bad that this kind of music can be played with exactly the same results with a PSR 900 or with another mid-of-the-line arranger. Just try to ask yourselves: if you lived in Bavaria and played Schlager music 24 hours a day, would you need to pay 3000 euros to sound exactly like Voncken sounded in this demo?
2- Speaking of "bad reputation", here is a suggestion to open your eyes: go to a Forum like Keyboard Corner or Harmony Central, post a link to this video, ask the opinion of other keyboard players and watch what happens. Warning: be sure to wear an helmet and a bullet-proof vest.
I have nothing against arranger keyboards; those of you who know me (it's obvious that Bruno 123 isn't one of them) know that I have three of them: Korg PA2X Pro, Roland G-70 and Tyros 2 (in strict alphabetical order...

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Personally I loved the T3 demos by Martin Harris, James Sargeant or Peter Baartmans, but this one obviously falls into another category.