I think in the future, that these two worlds (synthesizers and arrangers) will merge as one, that we'll have workstations that we can call a synthesizer and an arranger, So we can use styles and arpeggiators together, and advanced synth editing features, sampling, expansion slots etc.
That Fantom XR looks intresting, I've seen prices on German online stores, it costs around $1299, pretty cheap, considering all the features it has in store

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Greetz

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Marcel