It really depends on your terrain/location. I had posi's (LSD) front and rear on 31" MT's. I went everywhere I needed down here in the Everglades. If I was a hardcore mud bog racer, lockers and swampers would be better. But just for getting out, driving around and moderate wheeling, my setup worked.

 

Remember to get a winch. That stuff can get you in, but can't always get you out