From what I've heard, the main complaint about the V3 is that they are much louder than the V2. If you can hear the gears over the motor sound then it's too loud. I tried a set myself, there's a video around here somewhere, and I decided right away that I would stick with the V2. Your failure is the only V2 gearbox failure that I've heard of yet. I've literally installed dozens of the V2 gearboxes and I've never had a single one fail. And the V3 just won't be able to give you scale speed. A real leopard can hit at least 45 miles per hour, with the V3 gearboxes your scale top speed probably won't be over 25 or 30 miles per hour.