I'm running two GBoxes, one to a 3 m with an Ajak HH motor and one to a 1.8 m with a Moteck HH motor. Since I installed them, they've functioned perfectly. It's nice to have twice as many counts to work with as compared to a VBox. When I finally get around to putting up my 2.4 m, it will get another GBox even though I have an extra VBox lying around unused.
The only downside I've found is Gboxes are mechanically under-engineered. Both of my Gboxes arrived with their power transformers sheared off the plastic mounts at the bottom of the cases. The transformers are fairly heavy, had bounced around in shipment and had broken off the display PC boards, ruining the interface connector traces. In one of the units another PC board was badly damaged. The Gboxes were also under-packed at the factory and one remote was smashed into several pieces. The carrier was certainly to blame for the abuse, but that's to be expected. There was no visible damage to the outer shipping box itself. A small piece of foam compressing the transformer from the top of the GBox case would have prevented such a disaster.
Because the Gboxes were hard to get at the time, I decided to repair the units. I wouldn't want to do that again. It took a couple of hours, and while both units work, one is slightly blind to IR. Before the Gboxes arrived, I had wired up the control cables with watertight connectors, so I could haul a GBox out to the dishes when I worked on them. Unfortunately the GBoxes are too fragile in my mind to do this. I've largely worked around the problem by using my laptop to control the GBoxes from Linux remotely, but it's not as convenient.