Loving this new direction of the thread.

ultegra di2 rd: ~$250 in 2020C.E.
DA di2 rd: ~$600 in 2020C.E.

regardless of the cost of a motor, it certainly would be a pain to replace. You’d have to be a serious tinkering fetishist to want to undertake that, even if the motor costs only $5, rather than to just buy a new derailer (or since were talking about 8-16 years into the future when compatability becomes a question, just get a new groupset).

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I still vote Rohloff.

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