The version from CST is much nicer. It is teflon coated, so the Carbon pushrods travel much smoother through the teflon coated sleeves than they do the standard plastic ones. It is worth the extra money. My VF3 I'm flying now has the standard central one and it works...and with a servo I doubt you really see a difference, but compared to the one in my old Mantis that is teflon coated, you can feel the difference in the two if they are side by side.

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