Yep, what West said is very true. If I had to shoose between the two, I would go with the 14 bolt. It does limit ground clearance a little bit more, but sure is a lot harder to break a 14 bolt.
I've got a 10.5" 14 bolt on the rear of my Chevy pickup, which has a bored/stroked 454, 44" Swampers, 5.71 gears, heavy right foot, etc, etc, and I have never had any problems with it.
By the way, there are 2 14 bolts. One has a 9.5" ring gear, and the other is a 10.5".