I got to try out the "Downhill Assist" option today. Wow. It actually worked!! Really really well!! If you're not familiar with it, how it works is this: (see owners manual for full/accurate breakdown)..
Jeep must be in 4 LOW mode
Engage the downhill assist mode (see pic)
Put vehicle in 1st gear: This will limit your forward speed to approx 1-3 mph
Put vehicle in 2nd geer: This will limit your forward speed to approx 3-5 mph
Put vehicle in Drive: This will limit your forward speed to approx 5-8 mph
See owners manual for exact speed breakdown...
The speed is governed by the use of the brakes... It's basically automatic brake control..
Anyway, it works great!! Used it on some really steep descents today... I'm a bit of a control freak so I'm not sure if I really would use it all the time. Also, I don't see the "serious" offroader using it. Still, kinda fun to mess with if you have the chance...