It comes down to convenience. Having a limited slip center diff just means that for most situations the limited slip is good enough. Having done trails with a few RRCs, they just drive their trucks whereas I have to decide whether I have to lock my cdl before attempting an obstacle.
It's a very big convenience issue, indeed.
It sounds stupid at first, but not having to fuck with that lever is a good thing. Sometimes it's far better to be without the center locked. You occasionally come across a tiny spot where an open diff will stop you, though.
If that happens in the middle of the sand or mud, or if you break through a hard surface into oozy crap underneath, it can be too late. You don't want to run locked all the way through, but all of a sudden you need it.
In an ideal world, you'd use the lever and lock the center differential quickly. The world, however, is not ideal. You're going to have to fuck with it a bit, because you need it to work all of a sudden.
The damned thing will work in the driveway every time, but because you need it now, you'll have to fuck with it. Of course, while the universe is busy fucking you, you'll invariably go from needing to pull a lever to needing to exit the vehicle.
Cheers,
Kennith
I must say reading through this thread has now made me make plans to get unpissed off at my ole rover and straighten out a few things, and yank on some of her hoses, she'll be happy.