Do you have an application where you don't want automatic self leveling?
If you don't have an automatic self leveling system, you and your eye hand coordination are the self leveling system. Otherwise, you can end up dumping your bucket contents out the back of the bucket as you rais the FEL up to full height. If you're lucky, whatever that is drops in front of the tractor. If you're unlucky, it drops on the hood. If you're really unlucky and the loader lifts high enough, it might even drop and roll far enough to reach you!
Remember that with a mechanically self leveling FEL, whatever dump/crowd angle you set while the bucket is on the ground STAYS fixed automatically as you raise the FEL arms. For instance, if your bucket is crowded back to an angle of, say, 40 degrees with respect to the horizontal, it will stay at 40 degrees with respect the horizontal throught the entire lift range of the FEL with no operator input other than to just run the FELs raise/lower circuit. Another place where MSL is very nice to have is with a set of pallet forks. Set them level or just slightly above level when you pick up a pallet and the pallet stays at that angle through the entire FEL lift range. Without MSL, you have to constantly adjust the angle of the forks as you raise and lower the FEL.
Myself, if available, I will try very hard to an MSL FEL on my next go around. Or, some manufactures offer hydraulic self leveling (HSL). Usually it is active only while raising the FEL arms, although I've seen some newer FELs that offer HSL on both raising and lowering of the FEL.
Yes, MSL and HSL do cost more, but you have to remember to amortize that cost over 20+ years of ownership. Is automatic self leveling on a loader essential? Nope. Does it make FEL loader use easier and more productive? Yep!
