I wasn't aware of the Neptune gearboxes, so that could certainly be an option if weight is an issue or I don't need as much power. Would you say they are similar to the typical drill motor/gearbox in terms of power, as I understand the Saturns are much more powerful than this? Either way I finally have the ball bearings out and the drill motor/gearboxes locked up. I can have a run around with these when I get the rest of the bits and then make a decision on final motors/gearboxes from there.