Hi all, I have a JCW head that I'm reconditioning. Guides have already been replaced. The shop can supply TRW or AE. ECS and Pelican both have Intervalves. OEM is also an option.

Folks over on rennlist seem to like TRW for their Porsches but complain that TRW quality is gone down.

Looking for some opinions and past experience replacing exhaust valves on the W11. Thanks!