IMHO COG is fairly important as well. Gaining clearance without sacrificing COG is the real trick.Good discussions here.
On the driveshaft comment, I took our 80-series across the Con with the WWOR arms and our shaft was in great condition at the end. One is always conscious of the rear diff placement anyway and it's a priority to avoid contact, as it is a sure detriment to progress if hung on a rock, not to mention yoke, driveshaft or even major pumpkin damage.
On the clearance being "minimal"--not at all, we're actually talking a minimum of 3 1/2 inches of additional clearance. I just went out and measured and the high point of the WWOR bar is approximately 14 1/2 inches off the ground at its curve point. I'd LOVE to have 3 1/2 more inches of clearance under my Cruiser as a whole (heck, who wouldn't?), but without upgrading our 35" tires to 39's it's kinda hard. But 3.5 inches (minimum) of additional clearance is pretty substantial in the wheeling world.
Point in fact: look at the clockable transfer case adapters Marlin sells. You gain 1 3/16" clearance with it. Marlin's rotated crossmember gets you 3" inches more clearance. Clearance is the name of the wheeling game--or at least a major part of it--and many parts are made just for this reason.
I just don't see the point in hanging up on ANY rock. Any impact hurts progress.
The one time impacting rocks can be beneficial is when you ride your slider over a rock and use that action to pivot your rig through a tight turn. Probably not a maneuver the average 100 owner will have much occasion to use.

I just got riled over him saying the review was some kind of sellout trade of a product for a feature story. If they would have failed on the Rubicon, everyone, especially me, would have known about it, and written it. It's all good.
Hurry with the installation pics!