Both sold as 24 mm, Omega actual width 23,5 mm, Zenith 24,5 mm, loft 48 mm vs 57 mm. Both break in without any need for a special method just shave away. Both loose hair initially. The Omega loft of 48 mm is short for a 24 mm boar making brush dense focusing on backbone and scrub. The 57 mm loft is making Zenith knot a bit floppier but still with a typical boar feel. Note: Zenith also sell bleached boars with the same loft and they are way too floppy for me. The big Zenith will create lather quicker than the tiny Omega. Price is about 5 pounds each. I will keep both but probably try to move at least Omega knot to another handle when I get the time and energy to make one.