These trannys look a lot more substantial than the older model. They are equipped with helical gears vs the older model spur gears. Helical gears are able to handle more load/force because they have more teeth in contact at any one time. They are also substantially quieter than spur. The only down side is that they offer a bit more resistance/friction (because more teeth in contact) but with 2500ccs and tonnes of torque..... who cares
Time will tell...