A meaningful difference, for some, is the longevity of the grease. Polyurea greases last substantially longer than most. They are recommended for applications in which service intervals are long or irregular. Most other greases age, degrade, harden, while the polyurea greases remain sound.
Lucas polyurea grease can be found in the auto section at WM, and elsewhere, in grease gun cartridges, for peanuts. It's often used on farm machinery, and is a favorite among farmers. Their requirements and conditions of use tend to be much more demanding than cyclists'. So I'm fine with that grease.
Last edited by Bikesplendor; 03-05-19 at 08:26 AM.