[InFlight]

We used both Vex ball shifters and various Andy Mark fixed and shifting gearboxes over the past few years. They both work very reliably.

The choice for us often comes down to the available ratios and the size of tires we are using that year. The Andymark 4:1 and Vex 3.65:1 are great options. We like having ~ 16 ft/s on the high end, and as low of a pushing gear as we can get.

The only downside of the Vex gearboxes is the indirect encoder mounting with plastic gearing. With the AM gearboxes it's easier to 3D print an encoder bracket and use any encoder you like.

With either shifting gearbox (3 stage vex) or any AM it's trivial to make custom output shafts on a lathe with 7075 hex stock.

With all of them, attention to detail during assembly and liberal use of grease goes a long way.