I love the B mode engine braking but really wish I could control the "gear ratio". It works well for normal steep paved roads where it'll keep the vehicle at 50 mph or less. There's a very steep dirt road where I live (Red Grade near Sheridan, WY) that I can take my Odyssey minivan up and down as long as I'm careful with letting the brakes cool and using 1st gear in the 4-speed automatic transmission to keep the speed very low (< 15 mph). The Prius is the smartest car I've ever owned yet if the brake/engine combination isn't enough for this slope, the car is eventually totalled in a fireball when I hit the bottom of the hill at 110 mph after the brakes fail. I drive the car everywhere and have 28k miles in 10 months of ownership. This slope is only 4 miles long but is referred to by most as a 4WD road because of the slope. Several cars and trucks overheat their brakes and run off the side every year sometimes resulting in death. A world of exploration is opened up if I can figure out how to get down that slope in my Prius! I've done 25% of the hill and turned around to give it a try. Sure enough - the Prius engine braking is not useful on that slope so I'm dependent on brake regen and brakes to keep the speed in check. That is not good enough. Anyone have useful thoughts on this subject?