SB rockers hitting springs and retainers

Gtsdude, I read a post on this site saying the 273 rockers quickly and constantly fall out of adjustment. Any truth to that? That is why I was thinking about the Speedmaster part. I am not a person who thinks inexpensive automatically means bad. I'd be interested in hearing stories about defects, design flaws and parts failures in Speedmaster parts. It it helpful to know why to avoid a manufacturer. Have you had any bad Speedmaster experiences or heard about any?