Ti. retainers are a wear item and should be checked every 10k, does not matter the brand. For a high boost app use a spring setup with around 80 lbs seat pressure. Ferrea is a very good valvetrain as well as supertech, and omni. Skunk2's new pro series stuff is also really good.
Well said. My Super Tech retainers started to crack. Doesnt mean they are bad quality. I have 10,000 hard miles on them. Switching to complete Ferrea in the new head