I spent a lot of money having the SRM bearing conversion done. The bearing broke up after 13,000 miles, I bought a new one from Canada, the suppliers told me a 1% failure rate is acceptable. I rebuilt my '54 Golden Flash with the standard bush, and after over 8000 miles it's perfect. My feeling is, if I was going to race it or use my bike as every day transportation, and lived on the west coast of Wales, I would consider it. But as a pleasure bike and changing oil as frequently as 500 miles, don't bother.