I know this thread is about the E-Z Lube system. My only experience is with a similar product on AL-KO axles, which has since been bought out by Dexter. Northwood Manufacturing has been using them and our '13 trailer along with many others had brakes covered with grease from seal failures. Myself and many others never added grease via the zerk and Northwood claim the axle and hubs were assembled and greased at the AL-KO plant next to their factory. I could tell I had lost some breaking power and decided to do a complete tear down seal replacement and hand pack earlier this year with less than 7,500 miles on our trailer. 3 of the 4 wheels had seal failures with brakes covered in grease. AL-KO may had some bad installers at their factory we will never know. But I picked our trailer up 5 miles down the road from the factory and I know I never added grease. Maybe they used bad seals. But for what it is worth I plan to manually inspect my wheels myself every 2 years and do a repack myself.
Good luck to all of you, a bearing failure on the road would be no fun.