The clips i have seen of guys riding the duotone foil assist, the riders seem to ride with allot more flow and style than guys with the FD battery bolted onto the board, even the really good riders on FD & Manta you notice a difference in their turns when riding a wave compared to when they have no battery weight on the board.
I think the duotone controller is good, as it seems more aimed to get you up and going on a wave, then disappear so you can be hands free rather than holding a remote the whole time, motoring back out on foil constantly doing circuits in the lineup. The duotone setup seems to be more aimed at an assist for purists to get onto a wave disengage, then pump back out, or cruise back out to the lineup prone and use it as a paddle assist. If you want to be motoring around the whole time with a remote in your hands, you might be better with a FD or Manta type setup with a big heavy battery bolted on your board, just my 2c

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