I climbed the same "waterfall" section of Death Valley that Top Gear did in their "Trailer" episode... the part where they climbed up the rocky section that destroyed the trailers.
It was a walk in the part, crawled right up without any issues... keep in mind this is with an '11 though. The old "hold the brake" trick works well to keep both front wheels crawling together, so it wasn't a terrible issue not having the TORSEN at the time.
Would be nice to have it though... sounds like those guys had a blast. The Jeep guys that were with me were VERY impressed with the Raptor! There was one part that I went right up, that a Jeep took a few runs to get up... it's not a bad crawler, given you have the clearance.