A rear locker in a 2WD can be useful on boat ramps though...

 

lets not forget though, a locker locks the wheels together when straight , but when turning itll still let the wheels differentiate, and they can be relatively un expensive, I'm getting a Spartan locker for under 300, I've seen them as low as 215

 

That's an auto locker I believe? Don't the Arb/Aussie and elec lockers lock solid until disabled?

 

Yes they do. The auto lockers like a true track system will free up when not under a load. The electronic lockers are a posi lock that will only unlock when disabled/turned off. When the e-locker is on going around a corner, you will get the hop like a 4x4 on pavement.