Is the Lawton tune-up and/or wooden cup replacements worth it ?

in_shore, thanks for that insight, I'll probably get the work done after your review.  best!

Stephentp I immediately noticed a very positive difference installing the Lawton designed damping rings , the wood cups are a definite bonus further refining the sound and they do exactly what the manufacturer claim . I purchased the TH900 slightly used with Moon Audios top silver cable installed.

I’m fairly new to using headphones and headphone amplifiers I borrowed a few to try from an huge headphone enthusiast . The Lawton upgrade package was a shot in the dark I thought I’d try and happily it worked out very well .

Thansk for your response.  Did you by chance get to sample the sound comparison with TUNE UP with the stock cups?  I don't plan to change the cups.  Best!

Also, are you using the stock TH900 cable or upgraded that too?

Stephentp I just took delivery of the Lawton Audio tuneup kit and replacement cups in museum grade Mexican Bocote for my Fostex TH900s .
It made a significant difference for the better that’s for sure .