I used them on my 5er. No problems with seals or brakes.
I followed Dexter instructions carefully. Pumped slowly with a manual hand grease gun, continuously turning the wheel while pumping to ensure the grease gets thru the inner bearing with minimal pressure, and pumping until I saw new grease coming out the front. It did take a lot of grease.
Anyone saw me probably wondered what the heck I was doing sitting on a box, one leg up in the air turning the wheel with my foot, while I used two hands to pump the manual grease gun.