From what I have read, seen, and been told, the Lockright would be better for what you are doing. Detroit was one of the first on the market, that is why they have such an industry wide reputation. Some of the draw backs are, harder unloading(which can snap lessor axles, and destroy diffs.), can feel very awkward when unloading, especially in precarious positions(rocks). It is really hard to beat the ease, and even, unloading properties of the LockRight. I realize that you won't be rock crawling with your rig, but I would definately think that you would want to preserve your D44, and D30. It is simply less stress on your components.
Of course this is just my opinion based on asking a lot of wheelers, friends, and professionals.