DMT hones are supposed to use monocrystalline diamonds, claiming they don't break down like the polycrystalline diamonds used by Eze-Lap and others. Both DMT and Eze-Lap bond the diamonds to a steel plate (with nickel IIRC) and there could be differeneces in the bond too.
My experience is DMT hones keep their aggression better than Eze-Lap. But the Eze-Laps, once they get to a certain point, continue to work OK, just not nearly as fast as when new.
Opinions differ about which is the better value. I think DMTs are better hones, but they are more costly, so.....???