Guys,
Thrust bearings should not be related to a soft head, this is only a head damper configuration issue.
Dampers may vary slightly from batch to batch but I've found that adding an additional thin shim to the head resolves the softness in the head.
I get email on a weekly basis, some complain of too tight dampers, some say they are too loose. In the end this is pilot preference and should be configured with more or less shims.
Thanks,
Matt