it's not that slow...i can't clock any of my overlands so i have no way of reporting mph speeds but an overland with bearings and a pn speedy is plenty fast
i also have pn s01, racing modified, atomic modified, mini-zracer o-bb, a-bb. they will not disappoint you but at the same time they were not ment to achieve the same speeds as the racers, not with the idler/main gear