LED Light Fixtures Needed

[CNCman]

I installed these round light fixtures in my office 23 years ago. After a few years the circular flourescent tubes went out and I replaced them. Those finally died and I bought these nifty LED replacements. They have 5 strong magnets on the back, I wired them in, stuck the magents to the back of the steel fixture and thought that was the ticket. They worked for about 2 years I guess, now, out of 8 fixtures I think two are burning constantly. Out of the other 6, I think half are completely dead and the other 3 are barely flickering. Does anyone know of a better solution? I'm trashing the old round fixtures. I still want LED's just, something thin that fit in that 4'' box and will last more than a couple years. Thanks